VITAMIN E
VITAMIN E
Vitamin E is essential to health and plays an important role in supporting brain, eye, cardiovascular, maternal and infant health, as well as protecting the skin.
Vitamin E is used in various applications in the dietary supplement, beverage and infant nutrition industry.
Vitamin E was discovered in 1922 by H. Evans and K. Bishop as essential micronutrient needed
It was named according to a consecutive alphabetical order preceded by the discovery of vitamins A to D.
Later vitamin E was called alpha-tocopherol, according to the greek term “tokos” childbirth, “phero” to bear, and -ol, indicating an alcohol
Vitamin E fights off free radicals on the skin, which are a result of daily environmental stressors like unprotected sun exposure and air pollution.
In fighting off free radicals, vitamin E helps protect the skin from damage.
Additionally, vitamin E has “moisturizing and healing” benefits, and helps to “strengthen skin barrier function
The term vitamin E describes a family of eight related, fat-soluble molecules.
A sufficient intake of vitamin E (alpha-tocopherol) is important as it functions as an antioxidant, protecting cells, tissues, and organs from the oxidative stress caused by ‘free radicals’.
Free radicals are responsible for the aging process and can lead to various health conditions such as heart disease and inflammatory diseases.
Vitamin E in oil and dry forms are suitable for all food and dietary supplement applications
Vitamin E, a fat-soluble compound found principally in certain plant oils and the leaves of green vegetables.
Wheat-germ oil is a particularly rich source of the vitamin.
Vitamin E, first recognized in 1922, was first obtained in a pure form in 1936; it was identified chemically in 1938.
A number of similar compounds having vitamin E activity and classified as tocopherols or tocotrienols have been isolated.
Vitamin E acts as an antioxidant (i.e., an inhibitor of oxidation processes) in body tissues.
It protects unsaturated fats in the body from oxidation by peroxides and other free radicals.
The possibility that vitamin E may help prolong an active life span by slowing the rate of oxidative destruction of biological membranes is under study.
The vitamin is used commercially as an antioxidant to retard the rancidification of fats, especially vegetable oils.
Vitamin E is a nutrient your body needs to support your immune system and help your cells to regenerate. It also has antioxidant and anti-inflammatory properties that make getting enough essential to your everyday health.
Vitamin E is most commonly known for its benefits for skin health and appearance. It can be applied topically to your face to reduce inflammation and make your skin look younger.
Many people also swear by the effects of topical vitamin E when it’s applied to the face overnight.
Other Names
Rovimix E
Vitamin E 50% Powder Feed Grade.
Vitamin E Acetate
Dl Alpha Tocopheryl Acetate
Dl-Alpha Tocopheryl Acetate 50% Powder
2H-1-Benzopyran-6-ol,3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-,acetate
Vitamin E Acetate Powder
DL-alpha-Tocopheryl acetate
To convert to vitamin E if the product is labeled as DL-alpha-tocopherol: multiply units by 0.9 to determine mg. To convert from mg to units, divide by 0.9.
Vitamin E Acetate is an active ingredient for use in cosmetic products for the skin and the hair.
Vitamin E Acetate is an in-vivo antioxidant, it protects the cells against free radicals and prevents the peroxidation of body fats.
Vitamin E Acetate is also an effective moisturizing agent and improves the elasticity and smoothness of the skin, and is particularly suitable for use in sun-protection products and products for daily personal care.
DL-Alpha tocopheryl acetate, or Vitamin E Acetate, is the stable form of Vitamin E most often used in cosmetic formulations for its skin care benefits.
Vitamin E protects cell membranes from damage by oxygen free radicals.
It can prevent premature aging of the skin induced by UV irradiation and lipid peroxidation.
Tocopherols and tocotrienols can rapidly scavenge lipid peroxyl free radicals by acting as chain breaking antioxidants, thus preventing them from reacting with other lipids.
This process is key to limiting the propagation of lipid peroxidation in membranes.
It should be noted that tocopherol has the potential to act as a pro-oxidant rather than an anti-oxidant when co-antioxidants like vitamin C are not available to neutralize the tocopherol radical and when oxidative stress is mild.
Naturally occurring vitamin E can be unstable in skin care formulations.
Alpha Tocopherol is susceptible to UV irradiation, being rapidly converted to tocopheroxy radicals that use up other anitoxidants.
Use of Vitamin E Acetate, an ester of alpha tocopherol helps overcome this limitation.
Tocopheryl acetate is bioconverted to its biologically active form, vitamin E, within the skin when applied topically.
Studies show that topical use of tocopherol and alpha tocopheryl acetate are more effective than dietary supplementation in increasing the vitamin E content of the skin.
Supported by numerous studies over the past few years, Vitamin E Acetate has been shown to increase the enzyme activity in the skin, prevent free radical induced skin damage, increase epithelisation of surface wounds and increase the moisturisation of the horny layer.
INCI: Tocopheryl Acetate
Dry Vitamin E-Acetate
Vitamin E is an important fat-soluble antioxidant and has been in use for more than 50 years in dermatology.
Vitamin E is an important ingredient in many cosmetic products. It protects the skin from various deleterious effects due to solar radiation by acting as a free-radical scavenger.
Experimental studies suggest that vitamin E has antitumorigenic and photoprotective properties.
There is a paucity of controlled clinical studies providing a rationale for well-defined dosages and clinical indications of vitamin E usage in dermatological practice.
Name: Tocopheryl acetate
Synonyms: 3,4-Dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-benzopyran-6-yl acetate; Vitamin E acetate
α-Tocopheryl acetate, also known as vitamin E acetate, is a synthetic form of vitamin E.
α-Tocopheryl acetate is the ester of acetic acid and α-tocopherol.
Vitamin E 500 BG
Chemical names of active ingredient all-rac-a-tocopheryl acetate, DL-a-tocopheryl acetate, DL-alpha-tocopherol acetate, all-rac-alpha-tocopherol acetic acid ester,racemic 5,7,8-trimethyltocol acetate
CAS-No. 7695-91-2
EINECS-No. 231-710-0
2H-1-Benzopyran-6-ol, 3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-, 6-acetate
Vitamin E is a fat-soluble vitamin which is important for normal immune system functions.
As an antioxidant Vitamin E helps protect against cell damage and helps maintain cellular functions.
Vitamin E also plays an important role for all life stages including pre-term infants, pregnant woman, children and elderly persons.
However, scientific studies indicate that vitamin E intake above recommended levels may have beneficial effects on the immune system, especially in individuals with compromised immune function, such as elderly persons.
Applications
Vitamin E acetate is used as a fortifying agent and dietary supplement in food.
Vitamin E acetate is used in dermatological products such as skin creams.
Vitamin E acetate is an alternative to tocopherol and provides protection against the suns ultraviolet rays.
Sources of vitamin E
Vitamin E is present in only small quantities in modern diets, since vitamin E-rich foods have high fat content (seeds, grains, plant oils) which many consumers try to ovoid.
Therefore, globally, a large part of the population has vitamin E blood levels below the desirable value.
Health Benefits of vitamin E
Vitamin E, referring to all compounds exhibiting biological activity of alpha-tocopherols, is an antioxidant that helps protect against cell damage.
It is located in cell membranes, where it protects fatty acids against oxidation and thus helps maintain cellular functions.
This yields a number of universally recognized health benefits.
Studies have shown the beneficial effects of vitamin E in various health areas, such as heart, brain and cognitive function, immunity, metabolic support and eye, liver and skin health.
Vitamin E also reduces the probability of pregnancy-related disorders.
Although recommendations vary from country to country, most populations have an insufficiency of vitamin E.
Regular intake of vitamin E supplements can be recommended if a person’s vitamin E blood levels are not optimal, or in order to maintain a good vitamin E status.
25 kg bag in box
Units
1 mg DL (=all-rac)-a-tocopheryl acetate= 0.455 mg D (=RRR)--tocopherol equivalent= 1 International Unit (IU)
Description
Vitamin E Acetate is a White to creamy-white powder with a characteristic mild odor.
Composition
Ingredients in descending order of weight:DL-alpha-tocopheryl acetate, modified starch, silicon dioxide.
Solubility
The product readily disperses in either cold (10 °C) or warm water, to form a stable cloudy dispersion.
C31H52O3 Molar mass 472.8 g/mol
Specification
Assay min. 50.0% DL (=all-rac)--tocopherylacetate (= 500 mg/g vitamin E) max. 57.5% DL (=all-rac)--tocopherylacetate (= 575 mg/g vitamin E)
For further information see separate document:
“Standard Specification” (not for regulatory purposes) available via BASF’s WorldAccount:
Regulations
The product meets the regulatory requirements for a vitamin E source in most countries.
However,regulations on the ingredients used in the respective countries and for the intended use have to be observed.
Bulk density: 0.4 – 0.5 g/ml
Stability
Stored in its unopened original packaging at room temperature (max. 25 °C), the product is stable for at least 24 months.
Storage/Handling
The product should be stored tightly sealed in the original packaging in a dry place at room temperature (max. 25 °C).
Applications
Food products:
The product is designed for use in food applications,dry premixes, and products requiring rapid and complete water dispersibility, such as instant beverages.
Note
Vitamin E 500 BG must be handled in accordance with the Safety Data Sheet.
Topical vitamin E
Vitamin E is available in cream form and as an oil for topical use. It’s added to many cosmetic products, including anti-aging creams, eye serums, sunscreens, and makeup.
Vitamin E easily absorbs into skin. Topical use via creams or other products may increase the amount of vitamin E stored within the sebaceous glands.
Products that contain both vitamin E and vitamin C may be less likely to dissipate quickly if exposed to UV light. An animal study reported in Nutrition and CancerTrusted Source indicated that topical use of vitamin E reduced acute and chronic skin damage caused by UV irradiation.
While vitamin E oil is very thick and hard to spread on skin, it can make an excellent moisturizer for dry, patchy areas of skin. Products containing vitamin E as an ingredient may be easier to apply for overall use on skin. Problem areas that are very dry, such as the cuticles and elbows, might benefit from topical application of vitamin E oil.
Many vitamin E supplements come in the form of capsules that can be broken open and used directly on dry areas
3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-benzopyran-6-yl acetate
EC Inventory
3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-benzopyran-6-yl acetate
CAS names: 2H-1-Benzopyran-6-ol, 3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-, 6-acetate
IUPAC names
2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-3,4- dihydro-2H-chromen-6-yl acetate
2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-3,4-dihydro-2H-1-benzopyran-6-yl acetate
2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-3,4-dihydro-2H-chromen-6-yl acetate
2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-3.4-dihydro-2H-chromen-6YL acetate
3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-benzopyran-6-yl acetate
3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-benzopyran-6-yl acetate
3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-benzopyran-6-yl acetate, DL-Alpha-Tocopheryl Acetate, Vitamin E Acetate
[(2R)-2,5,7,8-tetramethyl-2-[(4R,8R)-4,8,12-trimethyltridecyl]-3,4-dihydrochromen-6-yl] acetate
DL-alfa-Tocopheryl Acetate
dl-alpha-tocopheryl acetate
Trade names
dl-alhpa-tocopheryl acetate
Vitamin E Acetate
Vitamin E acetate
Alpha-tocopheryl acetate (ATA) is a specific form of vitamin E that’s often found in skin care products and dietary supplements.
It’s also known as tocopheryl acetate, tocopherol acetate, or vitamin E acetate.
Vitamin E is known for its antioxidant properties.
Antioxidants help to protect your body from damaging compounds called free radicals.
Normally, free radicals form when your body converts food into energy.
However, free radicals can also come from UV light, cigarette smoke, and air pollution.
In nature, vitamin E comes in the form of tocopheryl or tocotrienol.
Both tocopheryl and tocotrienol have four forms, known as alpha, beta, gamma, and delta.
Alpha-tocopheryl (AT) is the most active form of vitamin E in humans.
ATA is more stable than AT, meaning it can better withstand environmental stresses such as heat, air, and light.
This makes it ideal for use in supplements and fortified foods because it has a longer shelf life.
Where can I find tocopheryl acetate?
Cosmetics and supplements
You’ll find ATA in a variety of skin care products.
The antioxidant properties of vitamin E can help to prevent damage to skin caused by free radicals from UV exposure.
Vitamin E may also have an anti-inflammatory effect on the skin.
Due to its higher stability, ATA is also used in vitamin E dietary supplements.
When taken orally, ATA is converted to AT within the intestine.
Vitamin E is in most multi-vitamins, so be sure to check how much is in your multi-vitamin if you take one, before adding a supplement.
Foods
In addition to dietary supplements and cosmetic products, you can find vitamin E in the following foods:
green leafy vegetables, such as broccoli and spinach
oils, such as sunflower oil, wheat germ oil, and corn oil
sunflower seeds
nuts, such as almonds and peanuts
whole grains
fruits, such as kiwi and mango
Vitamin E is also added to fortified foods, such as cereals, fruit juices, and many spreads.
You can check food labels to see if vitamin E has been added.
If you want to increase your vitamin E intake, you should start by first increasing your intake of these foods.
Vitamin E-Acetate is a high-quality, reliable and safe to use vitamin E that is easy to add to all kinds of feed and pet food.
Vitamins are substances which are necessary for maintaining all body functions (growth, health, fertility, performance).
As a rule, the animal body cannot synthesize these natural biologically active substances itself, which is why they must be supplied with the feed.
Key benefits of vitamin E-Acetate
Essential for cellular metabolism (cell respiration and nucleic acid metabolism).
Acts as an antioxidant, suppressing the autoxidation of unsaturated fatty acids and vitamin A in vivo.
Consistent high-quality and reliability
Easy to add to all kinds of feed and pet food
α-Tocopheryl acetate is often used in dermatological products such as skin creams.
It is not oxidized and can penetrate through the skin to the living cells, where about 5% is converted to free tocopherol.
Claims are made for beneficial antioxidant effects.
α-Tocopheryl acetate is used as an alternative to tocopherol itself because the phenolic hydroxyl group is blocked, providing a less acidic product with a longer shelf life.
It is believed that the acetate is slowly hydrolyzed after it is absorbed into the skin, regenerating tocopherol and providing protection against the sun’s ultraviolet rays.
Tocopheryl acetate was first synthesized in 1963 by workers at Hoffmann-La Roche.
Although there is widespread use of tocopheryl acetate as a topical medication, with claims for improved wound healing and reduced scar tissue, reviews have repeatedly concluded that there is insufficient evidence to support these claims.
There are reports of vitamin E-induced allergic contact dermatitis from use of vitamin E derivatives such as tocopheryl linoleate and tocopherol acetate in skin care products.
Incidence is low despite widespread use.
Chemistry
At room temperature, α-tocopheryl acetate is a fat-soluble liquid.
It has 3 chiral centers and thus 8 stereoisomers.
It is made by esterifying α-tocopherol with acetic acid.
2R,4R,8R-isomer, also known as RRR-α-tocopheryl acetate, is the most common isomer used for various purposes.
This is because α-tocopherol occurs in the nature primarily as RRR-α-tocopherol.[2]
α-Tocopherol acetate does not boil at atmospheric pressure and begins to degrade at 240 °C.
It can be vacuum distilled: it boils at 184 °C at 0.01 mmHg, at 194 °C (0.025 mmHg) and at 224 °C (0.3 mmHg).
In practice, it is not degraded notably by air, visible light or UV-radiation. It has a refractive index of 1.4950–1.4972 at 20 °C.[1]
α-Tocopherol acetate is hydrolyzed to α-tocopherol and acetic acid under suitable conditions or when ingested by people
Vitamin E (Synthetic)
Name
Vitamin E 500 BG
Vitamin E 500 FG
Vitamin E DL alpha Tocopherol
Vitamin E-Acetate (DL alpha Tocopherol)
Vitamin E-Acetate 98%
Dry Vitamin E-Acetate 50% DC/GFP
Dry Vitamin E-Acetate 50% DC
INCI name Tocopheryl Acetate
Synonyms DL-alpha-tocopheryl acetate, DL-alpha-tocopherol acetate, all-rac-alphatocopherol acetate, racemic 5,7,8-trimethyltocol acetate
Molecular formula C31H52O3
Molar mass 472.8 g/mol
CAS-No. 7695-91-2
EINECS-No. 231-710-0
Description Light yellow, viscous oil with practically no odor.
Solubility: Miscible with hydrocarbons, alcohols, fats and oils; insoluble in water
Specifi cations Parameter Requirement
Assay 96.5-102%
Identity Passes test
Lead max. 2 mg/kg
Appearance conforms
Optical rotation -0.01° to +0.01°
Acidity conforms
Related substances
(Ph.Eur. impurity A)
< 0.5 Area-%
Related substances
(Ph.Eur. impurity B)
< 1.5 Area-%
Related substances
(Ph.Eur. impurity C)
< 1.5 Area-%
Related substances
(Ph.Eur. impurity D)
< 0.5 Area-%
Related substances
(Ph.Eur., any other impurity max. 0.25 Area-%)
conforms
Related substances
(Ph.Eur., total impurities)
< 2.5 Area-%
Monographs The product complies with the current Ph.Eur., USP, FCC and Jap. Ph. monographs and with the German regulations for food additives.
Application Vitamin E Acetate is an active ingredient for use in cosmetic products for the skin and the hair.
As an in-vivo antioxidant, it protects the cells against free radicals and prevents the peroxidation of body fats.
Vitamin E Acetate is also an effective moisturizing agent and improves the elasticity and smoothness of the skin.
Vitamin E Acetate is particularly suitable for use in sun-protection products and products for daily personal care.
Stability and storage
Vitamin E Acetate is stable towards heat and oxygen, in contrast to Vitamin E alcohol (Tocopherol).
Vitamin E Acetate is not resistant towards alkalis, as it undergoes saponification, or to strong oxidizing agents.
When Vitamin E Acetate is stored in the unopened original container at room temperature the product is stable for at least 36 months.
Synergy with Vitamin C: Results of in-vitro study
Introduction
This study is able to show the synergistic action of Vitamin E and Vitamin C working together as anti-oxidants in the human skin.
Living human keratinocytes (HaCaT cells) were chosen as an in-vitro model.
Due to the reduced stability of Tocopherol (Vitamin E) and Ascorbic Acid (Vitamin C) in cosmetic formulations pro-drugs are used, typically Vitamin E Acetate and Sodium Ascorbyl Phosphate, respectively.
They were therefore used in this invitro cell test.
The HaCaT-cell system contains the esterases and phosphatases needed to convert the pro-drugs into the active form.
Sodium Ascorbyl Phosphate is water soluble and can be used as such in this aqueous cell system.
Vitamin E Acetate is insoluble in water and has to be brought into solution with a vehicle.
To keep the conditions as simple as possible, ethanol was used as vehicle.
Vitamin E Acetate was dissolved in 0.1% ethanol. A control experiment ensured that the vehicle (0.1% ethanol solution in water) has no disturbing effect.
Due to different kinetics of the cleavage of the prodrug into the active form, the optimum reaction time had to be determined empirically in preliminary experiments.
It could be shown that a reaction time of 48 hrs. for Sodium Ascorbyl Phosphate and 7 days for Vitamin E Acetate are the ideal conditions. (The compounds are stable in water during this time.)
If a combination was tested, Vitamin E Acetate supplementation started 5 days before adding Sodium Ascorbyl Phosphate.
Results
Human keratinocytes (HaCaT-cells) were supplemented with Vitamin E Acetate (VEA) diss. In 0.1% ethanol for seven days and/or Sodium Ascorbyl Phosphate (SAP) for 48 hrs.
The following concentrations were tested alone and in combination with the other active ingredient.
VEA: 3, 10, 30, 100, 300 micromolar
SAP: 50, 100, 200, 400 micromolar
The anti-oxidant effect was determined in measuring the ability to inhibit hydrogen-peroxide induced oxidation.
The cells were incubated with the fluorescence label DCFH.
The oxidative stress was induced with 200 micromolar hydrogen peroxide. (These are very harsh conditions.)
The capability of VEA and SAP to inhibit oxidation was measured in determing the resulting fl uorescence.
Tocopherols are a series of chiral organic molecules that vary in their degree of methylation of the phenol moiety of the chromanol ring. Tocopherols are lipid soluble anti-oxidants that protect cell membranes from oxidative damage. α-Tocopherol is the form of tocopherol preferentially absorbed by humans
Vitamin E is a vitamin that dissolves in fat. It is found in many foods including vegetable oils, cereals, meat, poultry, eggs, fruits, vegetables, and wheat germ oil.
It is also available as a supplement.
Vitamin E is used for treating vitamin E deficiency, which is rare, but can occur in people with certain genetic disorders and in very low-weight premature infants.
Vitamin E is also used for many other conditions, but there is no good scientific evidence to support these other uses.
The American Heart Association recommends obtaining antioxidants, including vitamin E, by eating a well-balanced diet high in fruits, vegetables, and whole grains rather than from supplements until more is known about the risks and benefits of taking supplements.
Vitamin E is an important vitamin required for the proper function of many organs in the body.
Vitamin E is also an antioxidant.
This means Vitamin E helps to slow down processes that damage cells.
Vitamin E
Foods rich in vitamin E such as wheat germ oil, dried wheat germ, dried apricots, hazelnuts, almonds, parsley leaves, avocado, walnuts, pumpkin seeds, sunflower seeds, spinach and bell pepper
Vitamin E is a fat-soluble vitamin with several forms, but alpha-tocopherol is the only one used by the human body.
Its main role is to act as an antioxidant, scavenging loose electrons—so-called “free radicals”—that can damage cells.
It also enhances immune function and prevents clots from forming in heart arteries. Antioxidant vitamins, including vitamin E, came to public attention in the 1980s when scientists began to understand that free radical damage was involved in the early stages of artery-clogging atherosclerosis, and might also contribute to cancer, vision loss, and a host of other chronic conditions.
Vitamin E has the ability to protect cells from free radical damage as well as stop the production of free radical cells entirely.
However, conflicting study results have dimmed some of the promise of using high dose vitamin E to prevent chronic diseases.
Food Sources
Vitamin E is found in plant-based oils, nuts, seeds, fruits, and vegetables.
Wheat germ oil
Sunflower, safflower, and soybean oil
Sunflower seeds
Almonds
Peanuts, peanut butter
Beet greens, collard greens, spinach
Pumpkin
Red bell pepper
Asparagus
Mango
Avocado
Signs of Deficiency
Because vitamin E is found in a variety of foods and supplements, a deficiency in the U.S. is rare.
People who have digestive disorders or do not absorb fat properly (e.g., pancreatitis, cystic fibrosis, celiac disease) can develop a vitamin E deficiency.
The following are common signs of a deficiency:
Retinopathy (damage to the retina of the eyes that can impair vision)
Peripheral neuropathy (damage to the peripheral nerves, usually in the hands or feet, causing weakness or pain)
Ataxia (loss of control of body movements)
Decreased immune function
Vitamin E is found naturally in some foods, added to others, and available as a dietary supplement.
“Vitamin E” is the collective name for a group of fat-soluble compounds with distinctive antioxidant activities.
Naturally occurring vitamin E exists in eight chemical forms (alpha-, beta-, gamma-, and delta-tocopherol and alpha-, beta-, gamma-, and delta-tocotrienol) that have varying levels of biological activity.
Alpha- (or α-) tocopherol is the only form that is recognized to meet human requirements.
Serum concentrations of vitamin E (alpha-tocopherol) depend on the liver, which takes up the nutrient after the various forms are absorbed from the small intestine.
The liver preferentially resecretes only alpha-tocopherol via the hepatic alpha-tocopherol transfer protein; the liver metabolizes and excretes the other vitamin E forms.
As a result, blood and cellular concentrations of other forms of vitamin E are lower than those of alpha-tocopherol and have been the subjects of less research.
Antioxidants protect cells from the damaging effects of free radicals, which are molecules that contain an unshared electron.
Free radicals damage cells and might contribute to the development of cardiovascular disease and cancer.
Unshared electrons are highly energetic and react rapidly with oxygen to form reactive oxygen species (ROS).
The body forms ROS endogenously when it converts food to energy, and antioxidants might protect cells from the damaging effects of ROS.
The body is also exposed to free radicals from environmental exposures, such as cigarette smoke, air pollution, and ultraviolet radiation from the sun.
ROS are part of signaling mechanisms among cells.
Vitamin E is a fat-soluble antioxidant that stops the production of ROS formed when fat undergoes oxidation.
Scientists are investigating whether, by limiting free-radical production and possibly through other mechanisms, vitamin E might help prevent or delay the chronic diseases associated with free radicals.
In addition to its activities as an antioxidant, vitamin E is involved in immune function and, as shown primarily by in vitro studies of cells, cell signaling, regulation of gene expression, and other metabolic processes.
Alpha-tocopherol inhibits the activity of protein kinase C, an enzyme involved in cell proliferation and differentiation in smooth muscle cells, platelets, and monocytes.
Vitamin-E–replete endothelial cells lining the interior surface of blood vessels are better able to resist blood-cell components adhering to this surface.
Vitamin E also increases the expression of two enzymes that suppress arachidonic acid metabolism, thereby increasing the release of prostacyclin from the endothelium, which, in turn, dilates blood vessels and inhibits platelet aggregation
itamin E is a nutrient that’s important to vision, reproduction, and the health of your blood, brain and skin.
Vitamin E also has antioxidant properties. Antioxidants are substances that might protect your cells against the effects of free radicals — molecules produced when your body breaks down food or is exposed to tobacco smoke and radiation. Free radicals might play a role in heart disease, cancer and other diseases. If you take vitamin E for its antioxidant properties, keep in mind that the supplement might not offer the same benefits as naturally occurring antioxidants in food.
Foods rich in vitamin E include canola oil, olive oil, margarine, almonds and peanuts.
You can also get vitamin E from meats, dairy, leafy greens and fortified cereals. Vitamin E is also available as an oral supplement in capsules or drops.
Vitamin E deficiency can cause nerve pain (neuropathy).
Vitamin E is a group of eight fat soluble compounds that include four tocopherols and four tocotrienols.
Vitamin E deficiency, which is rare and usually due to an underlying problem with digesting dietary fat rather than from a diet low in vitamin E, can cause nerve problems.
Vitamin E is a fat-soluble antioxidant protecting cell membranes from reactive oxygen species.
Worldwide, government organizations recommend adults consume in the range of 7 to 15 mg per day.
As of 2016, consumption was below recommendations according to a worldwide summary of more than one hundred studies that reported a median dietary intake of 6.2 mg per day for alpha-tocopherol.
Research with alpha-tocopherol as a dietary supplement, with daily amounts as high as 2000 mg per day, has had mixed results.
Population studies suggested that people who consumed foods with more vitamin E, or who chose on their own to consume a vitamin E dietary supplement, had lower incidence of cardiovascular diseases, cancer, dementia, and other diseases, but placebo-controlled clinical trials could not always replicate these findings.
As of 2017, vitamin E continues to be a topic of active clinical research.
There is no clinical evidence that use of vitamin E skincare products are effective.
Both natural and synthetic tocopherols are subject to oxidation, and so in dietary supplements are esterified, creating tocopheryl acetate for stability purposes.
Both the tocopherols and tocotrienols occur in α (alpha), β (beta), γ (gamma) and δ (delta) forms, as determined by the number and position of methyl groups on the chromanol ring.
All eight of these vitamers feature a chromane double ring, with a hydroxyl group that can donate a hydrogen atom to reduce free radicals, and a hydrophobic side chain which allows for penetration into biological membranes.
Of the many different forms of vitamin E, gamma-tocopherol (γ-tocopherol) is the most common form found in the North American diet, but alpha-tocopherol (α-tocopherol) is the most biologically active.
Palm oil is a source of tocotrienols.
Vitamin E was discovered in 1922, isolated in 1935 and first synthesized in 1938.
Because the vitamin activity was first identified as essential for fertilized eggs to result in live births (in rats), it was given the name “tocopherol” from Greek words meaning birth and to bear or carry.
Alpha-tocopherol, either naturally extracted from plant oils or, most commonly, as the synthetic tocopheryl acetate, is sold as a popular dietary supplement, either by itself or incorporated into a multivitamin product, and in oils or lotions for use on skin
Functions
Tocopherols function by donating H atoms to radicals (X).
Vitamin E may have various roles as a vitamin.
Many biological functions have been postulated, including a role as a fat-soluble antioxidant.
In this role, vitamin E acts as a radical scavenger, delivering a hydrogen (H) atom to free radicals. At 323 kJ/mol, the O-H bond in tocopherols is about 10% weaker than in most other phenols.
This weak bond allows the vitamin to donate a hydrogen atom to the peroxyl radical and other free radicals, minimizing their damaging effect.
The thus-generated tocopheryl radical is recycled to tocopherol by a redox reaction with a hydrogen donor, such as vitamin C.
As it is fat-soluble, vitamin E is incorporated into cell membranes, which are therefore protected from oxidative damage.
Vitamin E affects gene expression[17] and is an enzyme activity regulator, such as for protein kinase C (PKC) – which plays a role in smooth muscle growth – with vitamin E participating in deactivation of PKC to inhibit smooth muscle growth.
Deficiency
Main article: Vitamin E deficiency
Vitamin E deficiency is rare in humans, occurring as a consequence of abnormalities in dietary fat absorption or metabolism rather than from a diet low in vitamin E.
One example of a genetic abnormality in metabolism is mutations of genes coding for alpha-tocopherol transfer protein (α-TTP).
Humans with this genetic defect exhibit a progressive neurodegenerative disorder known as ataxia with vitamin E deficiency (AVED) despite consuming normal amounts of vitamin E.
Large amounts of alpha-tocopherol as a dietary supplement are needed to compensate for the lack of α-TTP Vitamin E deficiency due to either malabsorption or metabolic anomaly can cause nerve problems due to poor conduction of electrical impulses along nerves due to changes in nerve membrane structure and function.
In addition to ataxia, vitamin E deficiency can cause peripheral neuropathy, myopathies, retinopathy and impairment of immune responses.
Declining supplement use
In the United States vitamin E supplement use by female health professionals was 16.1% in 1986, 46.2% in 1998, 44.3% in 2002, but decreased to 19.8% in 2006.
Similarly, for male health professionals, rates for same years were 18.9%, 52.0%, 49.4% and 24.5%.
The authors theorized that declining use in these populations may have been due to publications of studies that showed either no benefits or negative consequences from vitamin E supplements.
Within the US military services, vitamin prescriptions written for active, reserve and retired military, and their dependents, were tracked over years 2007–2011.
Vitamin E prescriptions decreased by 53% while vitamin C remained constant and vitamin D increased by 454%.
A report on vitamin E sales volume in the US documented a 50% decrease between 2000 and 2006, with a potential reason being a meta-analysis that concluded high-dosage (≥400 IU/d for at least 1 year) vitamin E was associated with an increase in all-cause mortality.[24]
Side effects
The U.S. Food and Nutrition Board set a Tolerable upper intake level (UL) at 1,000 mg (1,500 IU) per day derived from animal models that demonstrated bleeding at high doses.
The European Food Safety Authority reviewed the same safety question and set a UL at 300 mg/day.
A meta-analysis of long-term clinical trials reported a non-significant 2% increase in all-cause mortality when alpha-tocopherol was the only supplement used.
The same meta-analysis reported a statistically significant 3% increase for results when alpha-tocopherol was used by itself or in combination with other nutrients (vitamin A, vitamin C, beta-carotene, selenium).
Another meta-analysis reported a non-significant 1% increase in all-cause mortality when alpha-tocopherol was the only supplement.
Subset analysis reported no difference between natural (plant extracted) or synthetic alpha-tocopherol, or whether the amount used was less than or more than 400 IU/day.
There are reports of vitamin E-induced allergic contact dermatitis from use of vitamin-E derivatives such as tocopheryl linoleate and tocopherol acetate in skin care products.
Incidence is low despite widespread use.
Drug interactions
The amounts of alpha-tocopherol, other tocopherols and tocotrienols that are components of dietary vitamin E, when consumed from foods, do not appear to cause any interactions with drugs.
Consumption of alpha-tocopherol as a dietary supplement in amounts in excess of 300 mg/day may lead to interactions with aspirin, warfarin, tamoxifen and cyclosporine A in ways that alter function.
For aspirin and warfarin, high amounts of vitamin E may potentiate anti-blood clotting action.
One small trial demonstrated that vitamin E at 400 mg/day reduced blood concentration of the anti-breast cancer drug tamoxifen.
In multiple clinical trials, vitamin E lowered blood concentration of the immunosuppressant medication, cyclosporine A.
The US National Institutes of Health, Office of Dietary Supplements, raises a concern that co-administration of vitamin E could counter the mechanisms of anti-cancer radiation therapy and some types of chemotherapy, and so advises against its use in these patient populations.
The references it cited reported instances of reduced treatment adverse effects, but also poorer cancer survival, raising the possibility of tumor protection from the intended oxidative damage by the treatments.
Supplements
Softgel capsules used for large amounts of vitamin E
Vitamin E is fat soluble, so dietary supplement products are usually in the form of the vitamin, esterified with acetic acid to generate tocopheryl acetate, and dissolved in vegetable oil in a softgel capsule.
For alpha-tocopherol, amounts range from 100 to 1000 IU per serving.
Smaller amounts are incorporated into multi-vitamin/mineral tablets.
Gamma-tocopherol and tocotrienol supplements are also available from dietary supplement companies.
The latter are extracts from palm or annatto oils.
Fortification
The World Health Organization does not have any recommendations for food fortification with vitamin E.
The Food Fortification Initiative does not list any countries that have mandatory or voluntary programs for vitamin E.
Infant formulas have alpha-tocopherol as an ingredient.
In some countries, certain brands of ready-to-eat cereals, liquid nutrition products and other foods have alpha-tocopherol as an added ingredient.[41]
Food additives
Various forms of vitamin E are common food additive in oily food, used to deter rancidity caused by peroxidation.
Those with an E number include:
E306 Tocopherol-rich extract (mixed, natural, can include tocotrienol)
E307 Alpha-tocopherol (synthetic)
E308 Gamma-tocopherol (synthetic)
E309 Delta-tocopherol (synthetic)
These E numbers include all racemic forms and acetate esters thereof.
Commonly found on food labels in Europe and some other countries, their safety assessment and approval are the responsibility of the European Food Safety Authority
Vitamin E is a fat-soluble antioxidant that is essential for the maintenance of healthy skin. Naturally occurring vitamin E is not a single compound; instead, vitamin E is a group of molecules with related structures, some of which may have unique properties in skin. Vitamin E is also found as vitamin E conjugates that increase stability but require cellular metabolism for activation. Vitamin E is normally provided to the skin through the sebum. Topical application can also supply the skin with vitamin E and may provide specific vitamin E forms that are not available from the diet. As an antioxidant, vitamin E primarily reacts with reactive oxygen species. In addition, vitamin E can also absorb the energy from ultraviolet (UV) light. Thus, it plays important roles in photoprotection, preventing UV-induced free radical damage to skin. Vitamin E may also have related anti-inflammatory roles in the skin. Other roles of vitamin E in the skin are poorly understood because research is limited. This article discusses the roles of vitamin E in the skin and summarizes the current knowledge about vitamin E in skin health.
Forms of vitamin E
The term “vitamin E” does not refer to a single molecule but to two classes of molecules with similar structures and antioxidant properties, comprising a family of eight substances. Tocopherols are the most abundant form of vitamin E in the body, consisting of four different forms (α-, β-, γ-, and δ-tocopherol). Tocotrienols, which are found in the body to a lesser extent, also exist in four different forms (α-, β-, γ-, and δ-tocotrienol). Although tocopherols and tocotrienols are available from the diet, α-tocopherol is the primary form of vitamin E found and maintained in the body, due to the specificity of a transport protein for α-tocopherol (see the article on Vitamin E).
Naturally occurring vitamin E is usually labeled as “natural” or “d” vitamin E, while synthetic vitamin E is a mixture of eight isomeric forms, usually labeled “all-rac” or “dl.” Tocopherols and tocotrienols are also available as ester derivatives that increase molecular stability upon exposure to heat, light, and air. Conjugated vitamin E molecules are typically used in dietary supplements; the esterified molecule is removed by cellular metabolism in the intestine. However, metabolism of vitamin E conjugates in skin is low; therefore, the availability of unesterified or “free” vitamin E from cutaneous application of conjugates may be limited (see Topical application).
Content and availability
Vitamin E is the most abundant lipophilic antioxidant found in human skin (1, 2). In humans, levels of vitamin E in the epidermis are higher than the dermis (1). Although the predominant form of vitamin E in skin of unsupplemented individuals is α-tocopherol, skin may also contain measurable amounts of γ-tocopherol (3) and other diet-derived tocopherols and tocotrienols (4).
Vitamin E first accumulates in the sebaceous glands before it is delivered to the skin surface through sebum (5, 6). Following oral ingestion, it takes at least seven days before the vitamin E content of sebum is altered (5, 7). There are no transport proteins specific for vitamin E in the skin. Sebum is secreted to the surface of the stratum corneum, where it concentrates in the lipid-rich extracellular matrix of this layer (3). Due to its lipophilic nature, vitamin E can also penetrate into all underlying layers of skin (8). Skin vitamin E levels are higher in individuals with increased sebum production, as well as in skin types that naturally produce more sebum (e.g., “oily’ skin on the face vs. drier skin on the arm) (1, 8).
Exposures to UV light (3, 9, 10) or ozone (6, 11, 12) lower the vitamin E content in skin, primarily in the stratum corneum. Vitamin E concentrations in the human epidermis also decline with age (1). Since epidermal structure changes with age (13), this may be due to increased UV penetration of this layer.
Topical application
Topical application of vitamin E has been used in a wide variety of forms throughout history, ranging from the application of oils to the skin surface to the use of modern cosmetic formulations. Just as sebum provides a delivery mechanism for vitamin E to the stratum corneum, topical applications of vitamin E permeate the epidermis and dermis (14, 15). The rate of percutaneous vitamin E absorption and factors that influence its penetration are largely unknown in humans, with a large range of concentrations and times used in various studies. It is generally assumed that solutions with vitamin E concentrations as low as 0.1% can increase vitamin E levels in the skin (16). Interestingly, vitamin E levels in the dermis increase greatly after topical application, likely accumulating in the sebaceous glands (15). However, although it is increased after topical delivery, the concentration of vitamin E in the dermis is lower than in the stratum corneum. Skin supplied only with dietary vitamin E primarily contains α- and γ-tocopherol (3, 7, 8); by contrast, skin supplied with synthetic vitamin E topically can contain a mixture of different tocopherols and/or tocotrienols (10, 15). In terms of penetration and absorption following topical application, tocotrienols and tocopherols accumulate in skin at varying rates, but the mechanisms governing these differences are unclear (15).
After topical application, vitamin E accumulates not only in cell membranes but also in the extracellular lipid matrix of the stratum corneum, where vitamin E contributes to antioxidant defenses. However, much of a topically applied dose of vitamin E alone will be destroyed in the skin following exposure to UV light (10). This suggests that although vitamin E is working as an antioxidant, it is unstable on its own and easily lost from the skin. Thus, improving the stability of topical applications with vitamin E is important. Products containing both vitamin C and vitamin E have shown greater efficacy in photoprotection than either antioxidant alone (see Photoprotection).
The stability of topical vitamin E solutions may also be increased by the use of vitamin E conjugates. These vitamin E derivatives are usually commercially produced esters of tocopherol (although tocotrienol esters have been formulated) that are resistant to oxidation but can still penetrate the skin layers. Vitamin E conjugates, however, do not have antioxidant functions. To be effective, the molecule conjugated to vitamin E must be removed by enzymes within a cell. Since the stratum corneum contains metabolically inactive cells and the remaining layers of the epidermis and dermis may contain a large volume of extracellular proteins, it is unclear how efficiently ester conjugates are converted to “free” vitamin E in skin. Depending on the compound and the model system used, the effectiveness of these formulations can vary greatly (16-20), and studies often do not compare the application of vitamin E conjugates to the application of unmodified vitamin E molecules.
Because vitamin E can absorb UV light to produce free radicals (see Photoprotection), there is the possibility that heavy sunlight exposure after topical application can cause skin reactions. However, concentrations of vitamin E between 0.1%-1.0% are generally considered safe and effective to increase vitamin E levels in the skin, but higher levels of α-tocopherol have been used with no apparent side effects (16). On the other hand, studies of dose-dependent vitamin E accumulation and effectiveness in skin protection are lacking. Some forms of vitamin E, especially ester conjugates, have led to adverse reactions in the skin, including allergic contact dermatitis and erythema. Although such reactions may be due to oxidation by-products, the emulsion creams used for topical delivery of compounds may also contribute to the observed effects (21).
Deficiency
Vitamin E deficiency may affect skin function, but there is little evidence from human studies. Vitamin E deficiency in rats has been reported to cause skin ulcerations (22) and changes in skin collagen cross-linking (23, 24), but the underlying cause of these effects is unknown.
Functions in Healthy Skin
Photoprotection
The primary role of vitamin E in the skin is to prevent damage induced by free radicals and reactive oxygen species; therefore, the use of vitamin E in the prevention of UV-induced damage has been extensively studied. Although molecules in the vitamin E family can absorb light in the UVB spectrum, the “sunscreen” activity of vitamin E is considered limited since it cannot absorb UVA light or light in higher wavelengths of the UVB spectrum (25). Thus, the primary photoprotective effect of vitamin E is attributed to its role as a lipid-soluble antioxidant.
Many studies in cell culture models (in vitro studies) have found protective effects of vitamin E molecules on skin cells (26-28), but these models do not recreate the complex structure of skin tissues. Therefore, in vivo studies are needed.
Studies using orally administered vitamin E have reported mixed results on its photoprotective potential.
An early study of vitamin E supplementation in hairless mice found no effect of dietary α-tocopherol acetate on UV-induced carcinogenesis (29).
Three other mouse studies reported inhibition of UV-induced tumors in mice fed α-tocopherol acetate (30-32), but one of these studies utilized vitamin E doses that were toxic to animals when combined with the UV treatment (30). Another study in mice found a reduction of UV-induced DNA damage with dietary α-tocopherol acetate, but no effects on other free radical damage were observed in the skin (33). One human study reported that subjects taking 400 IU/day of α-tocopherol had reduced UV-induced lipid peroxidation in the skin but concluded there was no overall photoprotective effect (34). This was supported by another human study that found that 400 IU/day of α-tocopherol for six months provided no meaningful protection to skin (35). Furthermore, multiple human studies have shown no effect of vitamin E on the prevention or development of skin cancers (36, 37).
In contrast to oral supplementation with α-tocopherol alone, multiple studies have found that the combination of vitamin C and vitamin E protects the skin against UV damage. Human subjects orally co-supplemented with vitamins C and E show increased Minimal Erythemal Dose (MED), a measure of photoprotection from UV light in skin (38, 39). The combination of the two vitamins was associated with lower amounts of DNA damage after UV exposure (40). Results of another study suggest a mixture of tocopherols and tocotrienols may be superior to α-tocopherol alone, as the mixture showed reduced sunburn reactions and tumor incidence after UV exposure in mice (41). However, further trials with dietary tocotrienol/tocopherol mixtures are needed in human subjects.
Topical application of vitamin E is generally effective for increasing photoprotection of the skin.
In rodent models, the application of α-tocopherol or α-tocopherol acetate before UV exposure reduces UV-induced skin damage by reducing lipid peroxidation (33, 42-44), limiting DNA damage (33, 45-47), and reducing the many chemical and structural changes to skin after UV exposure (14, 48-50). Vitamin E topical applications have also been shown to reduce UV-induced tumor formation in multiple mouse studies (14, 31, 51) and to reduce the effects of photo-activated toxins in the skin (52-55). Topical application of vitamin E also reduces the effects of UV radiation when applied after the initial exposure. In mice, α-tocopherol acetate prevents some of the erythema, edema, skin swelling, and skin thickening if applied immediately after UV exposure (49, 50). A similar effect has been shown in rabbits, where applying α-tocopherol to skin immediately after UV increased the MED (56). While the greatest effect was seen when vitamin E was applied immediately after UV exposure, one study showed a significant effect of application eight hours after the insult (49).
In human subjects, the use of vitamin E on skin lowers peroxidation of skin surface lipids (57), decreases erythema (58, 59), and limits immune cell activation after UV exposure (60).
Like oral supplementation with vitamin C and vitamin E, topical preparations with both vitamins have also been successful.
Together, the application of these antioxidants to the skin of animals before UV exposure has been shown to decrease sunburned cells (61, 62), decrease DNA damage (61, 63), inhibit erythema (61, 64), and decrease skin pigmentation after UV exposure (64). Similar effects have been seen in human subjects (65-67).
While a majority of studies have found benefit of topical α-tocopherol, there is much less evidence for the activity of esters of vitamin E in photoprotection (57).
As described above, vitamin E esters require cellular metabolism to produce “free” vitamin E.
Thus, topical use of vitamin E esters may provide only limited benefit or may require a delay after administration to provide significant UV protection.
Anti-inflammatory effects
Vitamin E has been considered an anti-inflammatory agent in the skin, as several studies have supported its prevention of inflammatory damage after UV exposure.
As mentioned above, topical vitamin E can reduce UV-induced skin swelling, skin thickness, erythema, and edema — all signs of skin inflammation.
In cultured keratinocytes, α-tocopherol and γ-tocotrienol have been shown to decrease inflammatory prostaglandin synthesis, interleukin production, and the induction of cyclooxygenase-2 (COX-2) and NADPH oxidase by UV light, as well as limit inflammatory responses to lipid hydroperoxide exposure.
In mice, dietary γ-tocotrienol suppresses UV-induced COX-2 expression in the skin.
Furthermore, topical application of α-tocopherol acetate or a γ-tocopherol derivative inhibited the induction of COX-2 and nitric oxide synthase (iNOS) following UV exposure
In vitro studies have shown similar anti-inflammatory effects of α- and γ-tocopherol on immune cells (73-75).
Many of these anti-inflammatory effects of vitamin E supplementation have been reported in combination with its photoprotective effects, making it difficult to distinguish an anti-inflammatory action from an antioxidant action that would prevent inflammation from initially occurring.
Despite these limitations, there are many reports of vitamin E being used successfully in chronic inflammatory skin conditions, either alone or in combination with vitamin C or vitamin D (79), thus suggesting a true anti-inflammatory action.
Wound healing
As mentioned above, skin lesions have been reported in rats suffering from vitamin E deficiency, although their origin is unclear.
Vitamin E levels decrease rapidly at the site of a cutaneous wound, along with other skin antioxidants, such as vitamin C or glutathione.
Since skin antioxidants slowly increase during normal wound healing, these observations have stimulated additional studies on the effect of vitamin E on the wound healing process.
However, no studies have demonstrated a positive effect of vitamin E supplementation on wound repair in normal skin.
Studies have shown that α-tocopherol supplementation decreases wound closure time in diabetic mice, but no effects have been observed in normal mice.
Vitamin E increases the breaking strength of wounds pre-treated with ionizing radiation, but this is likely due to antioxidant functions at the wound site akin to a photoprotective effect.
In contrast, intramuscular injection of α-tocopherol acetate in rats has been suggested to decrease collagen synthesis and inhibit wound repair.
In humans, studies with topical α-tocopherol have either found no effects on wound healing or appearance or have found negative effects on the appearance of scar tissue.
However, these studies are complicated by a high number of skin reactions to the vitamin E preparations, possibly due to uncontrolled formation of tocopherol radicals in the solutions used.
Despite these results, vitamin E, along with zinc and vitamin C, is included in oral therapies for pressure ulcers (bed sores) and burns.
Other functions
There is limited information concerning the effects of vitamin E supplementation on photodamage, which is commonly observed as skin wrinkling.
Although vitamin E can protect mice exposed to UV from excessive skin wrinkling, this is a photoprotective effect rather than treatment of pre-existing wrinkles.
Other reports using vitamin E to treat photodamage or reduce wrinkles are poorly controlled studies or unpublished observations.
An analysis of the dietary intake of Japanese women showed no correlation between vitamin E consumption and skin wrinkling.
Vitamin E and oils containing tocopherols or tocotrienols have been reported to have moisturizing properties, but data supporting these roles are limited.
Cross-sectional studies have shown no association between vitamin E consumption and skin hydration in healthy men and women.
However, two small studies have shown topical application of vitamin E can improve skin water-binding capacity after two to four weeks of use.
Long-term studies with topical vitamin E are needed to establish if these moisturizing effects can be sustained.
Environmental pollutants like ozone can decrease vitamin E levels in the skin and lead to free radical damage that may compound the effects of UV exposure.
Although not well studied, topical applications of vitamin E may reduce pollution-related free radical damage .
Conclusion
Vitamin E is an integral part of the skin’s antioxidant defenses, primarily providing protection against UV radiation and other free radicals that may come in contact with the epidermis. Oral supplementation with only vitamin E may not provide adequate protection for the skin, and co-supplementation of vitamin E and vitamin C may be warranted to effectively increase the photoprotection of skin through the diet.
However, topical vitamin E seems to be an effective mechanism for both delivery to the skin and providing a photoprotective effect.
Additional anti-inflammatory effects of topical vitamin E have been seen in the skin, although more studies are needed to determine if vitamin E primarily works as a free-radical scavenger or can have other effects on inflammatory signaling.
Vitamin E is available commercially as a variety of synthetic derivatives, but the limited cellular metabolism in skin layers makes the use of such products problematic. Use of unesterified vitamin E, similar to that found in natural sources, has provided the most consistent data concerning its topical efficacy.
The vitamin E family consists of eight different tocopherols and tocotrienols, and it will be important for future studies to determine if one or more of these molecules can have unique effects on skin function.
Vitamin E is an antioxidant that protects cells from damage and its lack is associated with neurological problems and anemia frequently found in CD patients.
Vitamin E consists of eight naturally occurring lipophilic compounds consisting of four tocopherols (α-, β-, γ-, and δ-) and four tocotrienols (α-, β-, γ-, and δ-) that differ in their side chain saturation and degree of methylation of their chromanol heads.
Vitamin E is most widely recognized for its antioxidant function that terminates the self-perpetuating cycle of lipid peroxidation.
Although α-tocopherol and γ-tocopherol are the most abundant vitamin E forms in the diet and in vivo, dietary requirements of vitamin E are currently limited to α-tocopherol because this is the only form that reverses vitamin E deficiency and no other vitamin E forms are interconverted to α-tocopherol in humans.
This article will therefore discuss the mechanisms regulating vitamin E bioavailability and metabolism as well as its antioxidant function and dietary essentiality.
Vitamin E has a fundamental role as an antioxidant in the metabolism of all cells.
Vitamin E is the generic descriptor for all tocopherol and tocotrienol derivatives exhibiting the biological activity of α-tocopherol.
Primary dietary sources of vitamin E include vegetable oils, seeds, and cereal grains.
Vitamin E is fat-soluble and requires micellularization for absorption.
It functions as a lipid-soluble biological antioxidant and protects against lipid peroxidation through the scavenging of free radicals.
It may also confer anti-inflammatory effects and function in enzyme regulation and gene expression.
Vitamin E deficiency is not common in humans and is manifest clinically as hemolytic anemia.
Vitamin E
R.S. Bruno, E. Mah, in Reference Module in Biomedical Sciences, 2014
Abstract
Vitamin E consists of eight naturally occurring lipophilic compounds consisting of four tocopherols (α-, β-, γ-, and δ-) and four tocotrienols (α-, β-, γ-, and δ-) that differ in their side chain saturation and degree of methylation of their chromanol heads. Vitamin E is most widely recognized for its antioxidant function that terminates the self-perpetuating cycle of lipid peroxidation. Although α-tocopherol and γ-tocopherol are the most abundant vitamin E forms in the diet and in vivo, dietary requirements of vitamin E are currently limited to α-tocopherol because this is the only form that reverses vitamin E deficiency and no other vitamin E forms are interconverted to α-tocopherol in humans. This article will therefore discuss the mechanisms regulating vitamin E bioavailability and metabolism as well as its antioxidant function and dietary essentiality.
Vitamin E
Gerald F. CombsJr. Ph.D., James P. McClung Ph.D., in The Vitamins (Fifth Edition), 2017
Abstract
Vitamin E has a fundamental role as an antioxidant in the metabolism of all cells. Vitamin E is the generic descriptor for all tocopherol and tocotrienol derivatives exhibiting the biological activity of α-tocopherol. Primary dietary sources of vitamin E include vegetable oils, seeds, and cereal grains. Vitamin E is fat-soluble and requires micellularization for absorption. It functions as a lipid-soluble biological antioxidant and protects against lipid peroxidation through the scavenging of free radicals. It may also confer anti-inflammatory effects and function in enzyme regulation and gene expression. Vitamin E deficiency is not common in humans and is manifest clinically as hemolytic anemia.
Vitamin E
J. Atkinson, … R. Parker, in Encyclopedia of Biological Chemistry (Second Edition), 2013
Abstract
Vitamin E refers to a group of structurally related, fat-soluble, plant-derived natural products comprised of tocopherols and tocotrienols. It is now accepted that vitamin E inhibits the free radical-chain peroxidation of polyunsaturated lipids in membranes and lipoproteins. The most biologically active form for mammals is α-tocopherol, which is the dominant form of vitamin E found in blood and tissues. The estimated average requirement of α-tocopherol for people is 12 mg d−1, but dietary intakes and plasma levels of α-tocopherol show considerable inter individual variation. The ability of vitamin E to prevent atherosclerosis, cancer, and central nervous system disorders, remains to be fully described. Aspects of absorption, intra- and intercellular transfer by specific proteins, and oxidative metabolism of the different forms of vitamin E obtained in the diet, are all likely important descriptors of final biological activity.
Vitamin E
Mark G. Papich DVM, MS, DACVCP, in Saunders Handbook of Veterinary Drugs (Fourth Edition), 2016
Instructions for use
Vitamin E has been proposed as treatment for a wide range of human illnesses, but evidence for efficacy in animals is lacking.
In animals, it is used as adjunctive antioxidant therapy for a variety of diseases.
To convert to vitamin E if the product is labeled as DL-alpha-tocopherol: multiply units by 0.9 to determine mg. To convert from mg to units, divide by 0.9.
To convert to vitamin E if the product is labeled as D-alpha-tocopherol: multiply units by 0.67 to determine mg. To convert from mg to units, divide by 0.67. For example, 1 unit of vitamin A is equivalent to 0.67 mg d-alpha tocopherol or 0.9 mg dl-alpha tocopherol.
There are several naturally occurring forms of vitamin E in plants.
Vitamin E is passively absorbed in conjunction with other lipid-soluble vitamins by the intestinal tract, and subsequently packaged into chylomicrons.
Vitamin E is the first and selenium the second line of defense against peroxidation of lipids contained in cell membranes.
Tocopherols act as antioxidants by breaking free-radical chain reactions. Vitamin C helps to regenerate the active form of vitamin E.
Vitamin E deficiency can result in erythrocyte fragility, muscular degeneration, steatitis, retinopathy, and reproductive failure.
Vitamin E excess appears to be non-toxic.
Vitamin E
R.S. Bruno, E. Mah, in Reference Module in Biomedical Sciences, 2014
Abstract
Vitamin E consists of eight naturally occurring lipophilic compounds consisting of four tocopherols (α-, β-, γ-, and δ-) and four tocotrienols (α-, β-, γ-, and δ-) that differ in their side chain saturation and degree of methylation of their chromanol heads. Vitamin E is most widely recognized for its antioxidant function that terminates the self-perpetuating cycle of lipid peroxidation. Although α-tocopherol and γ-tocopherol are the most abundant vitamin E forms in the diet and in vivo, dietary requirements of vitamin E are currently limited to α-tocopherol because this is the only form that reverses vitamin E deficiency and no other vitamin E forms are interconverted to α-tocopherol in humans. This article will therefore discuss the mechanisms regulating vitamin E bioavailability and metabolism as well as its antioxidant function and dietary essentiality.
Vitamin E
Gerald F. CombsJr. Ph.D., James P. McClung Ph.D., in The Vitamins (Fifth Edition), 2017
Abstract
Vitamin E has a fundamental role as an antioxidant in the metabolism of all cells. Vitamin E is the generic descriptor for all tocopherol and tocotrienol derivatives exhibiting the biological activity of α-tocopherol. Primary dietary sources of vitamin E include vegetable oils, seeds, and cereal grains. Vitamin E is fat-soluble and requires micellularization for absorption. It functions as a lipid-soluble biological antioxidant and protects against lipid peroxidation through the scavenging of free radicals. It may also confer anti-inflammatory effects and function in enzyme regulation and gene expression. Vitamin E deficiency is not common in humans and is manifest clinically as hemolytic anemia.
Vitamin E
J. Atkinson, … R. Parker, in Encyclopedia of Biological Chemistry (Second Edition), 2013
Abstract
Vitamin E refers to a group of structurally related, fat-soluble, plant-derived natural products comprised of tocopherols and tocotrienols.
It is now accepted that vitamin E inhibits the free radical-chain peroxidation of polyunsaturated lipids in membranes and lipoproteins.
The most biologically active form for mammals is α-tocopherol, which is the dominant form of vitamin E found in blood and tissues.
The estimated average requirement of α-tocopherol for people is 12 mg d−1, but dietary intakes and plasma levels of α-tocopherol show considerable inter individual variation.
The ability of vitamin E to prevent atherosclerosis, cancer, and central nervous system disorders, remains to be fully described. Aspects of absorption, intra- and intercellular transfer by specific proteins, and oxidative metabolism of the different forms of vitamin E obtained in the diet, are all likely important descriptors of final biological activity.
Vitamin E
Mark G. Papich DVM, MS, DACVCP, in Saunders Handbook of Veterinary Drugs (Fourth Edition), 2016
Instructions for use
Vitamin E has been proposed as treatment for a wide range of human illnesses, but evidence for efficacy in animals is lacking. In animals, it is used as adjunctive antioxidant therapy for a variety of diseases.
To convert to vitamin E if the product is labeled as DL-alpha-tocopherol: multiply units by 0.9 to determine mg. To convert from mg to units, divide by 0.9.
To convert to vitamin E if the product is labeled as D-alpha-tocopherol: multiply units by 0.67 to determine mg. To convert from mg to units, divide by 0.67. For example, 1 unit of vitamin A is equivalent to 0.67 mg d-alpha tocopherol or 0.9 mg dl-alpha tocopherol.
Vitamin E
In Meyler’s Side Effects of Drugs (Sixteenth Edition), 2016
Skin
Vitamin E and its derivatives (such as tocopheryl linoleate and tocopherol acetate) in skin-care products has been associated with allergic contact dermatitis.
In a systematic review of 931 cases of vitamin E-induced contact dermatitis, mainly from one large study, there were no deaths and only three patients required hospitalization for treatment.
The authors concluded that vitamin E-induced contact dermatitis is uncommon, despite its widespread use in skin care products.
A similar conclusion was reached in a retrospective analysis of patch-test data from 2950 patients who were tested from June 1987 to December 2007; only 18 (0.61%) had positive reactions to alpha-tocopherol; the incidence did not change with time
Vitamin E
Larry R. Engelking, in Textbook of Veterinary Physiological Chemistry (Third Edition), 2015
Abstract:
There are several naturally occurring forms of vitamin E in plants.
Vitamin E is passively absorbed in conjunction with other lipid-soluble vitamins by the intestinal tract, and subsequently packaged into chylomicrons.
Vitamin E is the first and selenium the second line of defense against peroxidation of lipids contained in cell membranes.
Tocopherols act as antioxidants by breaking free-radical chain reactions. Vitamin C helps to regenerate the active form of vitamin E.
Vitamin E deficiency can result in erythrocyte fragility, muscular degeneration, steatitis, retinopathy, and reproductive failure.
Vitamin E excess appears to be non-toxic.
Vitamin E
Martin Kohlmeier, in Nutrient Metabolism, 2003
Dietary sources
The most confusing aspect of vitamin E nutrition may come from the great diversity of compounds with some kind of related activity.
So far, 12 compounds with characteristic vitE activity have been identified: alpha-tocopherol, beta-tocopherol, gamma-tocopherol, delta-tocopherol, alpha-tocotrienol, beta-tocotrienol, gamma-tocotrienol, delta-tocotrienol, the tocotrienols d-P(21)-T3 and d-P(25)-T3 (Qureshi et al., 2001), alpha-tocomonoenol, and marine-derived tocopherol (Yamamoto et al., 2001).
Like all essential nutrients, a minimum level of vitamin E is required in the human diet to maintain optimal health.
Vitamin E deficiency is normally only observed in cases of severe malnutrition or in individuals with genetic defects in the α-tocopherol transfer protein (α-TTP; described later in this section) or conditions that affect fat absorption from the diet (Di Donato et al., 2010; Muller, 2010; Traber, 2007; Traber et al., 2008).
Severe vitamin E deficiency results in various neurological conditions including ataxia (impaired balance and coordination), myopathy (muscle weakness) and damage to the retina of the eye.
Suboptimal dietary intake or plasma levels of vitamin E have been associated with increased risk to cardiovascular disease, some cancers and decreased immune function (Knekt et al., 1994; Kushi et al., 1996; Wright et al., 2006).
However, the results of large-scale vitamin E intervention trials with at risk populations have been equivocal (Traber et al., 2008).
Vitamin E is an antioxidant, acting as a free radical scavenger and protecting against PUFA (polyunsaturated fatty acid) peroxidation in cell membranes
Vitamin E inhibits lipid peroxidation, thereby stabilizing cell membranes, and preventing changes in membrane fluidity and function
Vitamin E
Maret G. Traber, in Handbook of Oxidants and Antioxidants in Exercise, 2000
1 INTRODUCTION
Vitamin E is a chain-breaking antioxidant, which means that once lipid peroxidation begins, vitamin E stops it from progressing further. This antioxidant function is quite important with relationship to exercise because exercise increases the throughput of energy in the mitochondria and thereby increases the number of radicals escaping the electron transport chain.
Vitamin E requirements are dependent upon the degree of oxidative stress, the dietary polyunsaturated fatty acid (PUFA) intake and the intake of other antioxidants.
Furthermore, vitamin E activity is dependent upon an “antioxidant network” involving a wide variety of antioxidants and antioxidant enzymes, which functions to maintain vitamin E in its unoxidized state, ready to intercept and scavenge radicals [1].
This chapter will describe the antioxidant properties of vitamin E, its lipoprotein transport and delivery to tissues, and illustrate functional aspects with relationship to vitamin E in exercise.
Vitamin E consists of eight naturally occurring lipophilic compounds consisting of four tocopherols (α-, β-, γ-, and δ-) and four tocotrienols (α-, β-, γ-, and δ-) that differ in their side chain saturation and degree of methylation of their chromanol heads. Vitamin E is most widely recognized for its antioxidant function that terminates the self-perpetuating cycle of lipid peroxidation.
Although α-tocopherol and γ-tocopherol are the most abundant vitamin E forms in the diet and in vivo, dietary requirements of vitamin E are currently limited to α-tocopherol because this is the only form that reverses vitamin E deficiency and no other vitamin E forms are interconverted to α-tocopherol in humans.
This article will therefore discuss the mechanisms regulating vitamin E bioavailability and metabolism as well as its antioxidant function and dietary essentiality.
There are several naturally occurring forms of vitamin E in plants.
Vitamin E is passively absorbed in conjunction with other lipid-soluble vitamins by the intestinal tract, and subsequently packaged into chylomicrons.
Vitamin E is the first and selenium the second line of defense against peroxidation of lipids contained in cell membranes.
Tocopherols act as antioxidants by breaking free-radical chain reactions.
Vitamin C helps to regenerate the active form of vitamin E.
Vitamin E deficiency can result in erythrocyte fragility, muscular degeneration, steatitis, retinopathy, and reproductive failure. Vitamin E excess appears to be non-toxic.
Of the many skin-care ingredients out there, vitamin E is definitely one of the most common.
It’s found naturally in our bodies and in certain foods.
And if you look closely, you’ll probably find it in many of the skin-care products already in your medicine cabinet — serums, moisturizers, eye creams, and just about everything in between. You may have even tried taking vitamin E in supplement form.
Vitamin E may slow the aging process of cells
Vitamin E is an antioxidant, meaning it prevents free radicals from damaging cells. Free radicals are highly reactive molecules produced by chemical reactions in the body.
They can also come from outside sources like cigarette smoke and air pollution.
When free radicals damage cells, conditions like dementia and Alzheimer’s disease may develop.
Free radicals reduce a cell’s lifespan through a process called oxidative stress.
The process of oxidative stress as it relates to aging is not clear.
However, scientists do know that free radicals bind to cells in a way that causes damage to the protein and DNA inside.
As an antioxidant, vitamin E neutralizes this threat.
A 2018 paper in The Journals of Gerontology: Series A found that among 1,002 patients with clinically confirmed cardiovascular disease, low vitamin E consumption was linked to increased cellular aging.
Vitamin E can help those with macular dysfunction
Macular dysfunction is a genetic eye disease, and in severe cases, it can result in vision loss. The condition occurs when the macula region — an oval-shaped area at the center of your eye — is damaged by free radicals.
Two clinical trials in 2006 with about 4800 participants found that vitamin E in combination with other nutrients could reduce the risk of vision loss by 19%.
They also found that the vitamin E combo slowed the progression of macular dysfunction.
The study compared different supplements and how they affected the progression of macular dysfunction.
The researchers found that a supplement containing 400 IU of vitamin E — along with other vitamins like zinc oxide, copper, vitamin C, and beta-carotene — reduced the possibility of a mild case of macular dysfunction developing into a severe case.
Supplementation with only copper and zinc or antioxidants were not as effective.
It’s important to note that vitamin E is best suited to prevent progression of the disease in those who already have it.
It is not as effective at preventing age-related macular dysfunction in people who do not show symptoms of the disorder.
Vitamin E boosts immune system response
Vitamin E appears to boost levels of a type of immune cell called T lymphocytes or T cells, says Elizabeth Somer, MA, RD, a registered dietitian and medical advisory board member for Persona.
T cells are white blood cells that play a role in the immune system.
There are two types of T cells: regulatory and cytotoxic.
Regulatory T cells manage immune reactions to foreign particles and prevent autoimmune conditions like inflammatory bowel disease and type 1 diabetes.
Meanwhile, cytotoxic cells attach to cells infected by bacteria and viruses and kill the cells.
“Vitamin E helps maintain the strength and vitality of T cell membranes, helps these cells multiply correctly, and communicate to other immune processes.
T cells decrease with age, so maintaining optimal intake of this vitamin is important in maintaining a well-functioning immune system,” Somer says.
A 2018 paper published in IUBMB Life found that vitamin E deficiency hindered immune response by altering the functions of T cells and antibody production.
But, it also found that with vitamin E supplementation, these effects can be reversed.
Most research conducted on vitamin E’s role in immune response has focused primarily on T cells.
However, scientists believe vitamin E may regulate other types of immune cells too.
Vitamin E may slow memory loss in individuals with Alzheimer’s disease
Because the brain uses a lot of oxygen, it is highly susceptible to oxidative stress, says Debbie Petitpain, MS, RDN, a spokesperson for the Academy of Nutrition and Dietetics.
Since vitamin E can prevent cellular damage caused by oxygen, it may help prevent cognitive decline
A 2014 study published in JAMA with just over 560 Alzheimer’s patients found that having 2000 IU per day of alpha-tocopherol — a form of vitamin E — reduced functional decline.
The study tested cognitive function with daily activity assessment.
It’s important to note that all participants had only mild cases of Alzheimer’s.
Vitamin E may improve blood vessel health
Vitamin E plays a vital role in the production of red blood cells by protecting them from oxidative damage. Alongside
vitamin K
, it also helps expand blood vessels, which reduces the possibility of blood clots.
A 2007 paper published in Circulation found that in 213 patients who took 600 IU vitamin E daily, their risk of developing venous thromboembolism, a condition where a blood clot in the extremities travels to the lung, lowered by 21%.
While blood clotting is important because it slows bleeding after a cut or injury, it can be problematic when clots form in your blood vessels and then spread to the lungs or heart.
This can lead to severe chest pain, coughing, and difficulty breathing.
A 2013 paper in the Journal of Nutritional Biochemistry assessed 15 healthy men and found that vitamin E protects against the development of impaired lining of blood vessels caused by hyperglycemia after eating.
Vitamin E was effective in offsetting any spikes in blood pressure after eating, thus improving blood vessel health.
Another study conducted in 2013 assessed 30 smokers after they stopped smoking and began taking 500 mg of vitamin E daily.
It found that vitamin E supplementation along with quitting nicotine, resulted in about a 19% reduction in cardiovascular disease risk.
Those who took vitamin E supplementation saw reduced levels of inflammation and better vascular function compared to those who received a placebo.
Vitamin E may even help reduce premenstrual symptoms (PMS) like anxiety, depression, cramping, and even cravings.
A 2016 study published in the Iranian Journal of Nursing and Midwifery involving 86 women found that vitamin E supplementation reduced premenstrual symptoms like anxiety and depression more than the placebo group or those taking vitamin D
Meanwhile, a 2019 study with 210 female participants published in Obstetrics and Gynecology Science indicated that consuming vitamin E two days before menstruation through three days following may help alleviate menstrual cramps.
Vitamin E can even help with premenstrual cravings.
A 2013 study published in the Journal of the American College of Nutrition found that 75 women who consume between 150 to 300 IU of vitamin E a day experienced fewer cravings than normal during their period.
Vitamin E may prevent sunburn and UV damage
While Vitamin E cannot prevent sunburn on its own, it can be used alongside sunscreen for extra UV protection.
“For protection against photoaging of the skin and sunburns due to sun exposure, it is recommended to use sunscreen daily,” says Olabola Awosika, MD, MS, a dermatologist at Henry Ford Hospital in Detroit.
“Vitamin E can be used in conjunction with sunscreen to provide further benefit against oxidative damage from UV rays.”
While multiple studies conducted in animals from the early 2000s found that topical use of vitamin E provided an increased protection against skin cancer and reduced skin problems like hyperpigmentation and inflammation, evidence remains unclear in humans.
However, a 2009 paper published in the Journal of Investigative Dermatology suggests that combining vitamin C and E with sunscreen may prevent ultraviolet-related damage in comparison to using sunscreen alone.
Vitamin E refers to the plant-derived, lipid-soluble antioxidants: tocopherols and tocotrienols.
They terminate the chain reaction of lipid peroxidation.
Vitamin E biological activity is different from its antioxidant activity, and there is a preference for α-tocopherol.
This preference is achieved through the selective degradation and excretion of other vitamin E forms and the selective retention of α-tocopherol, mediated by the hepatic α-tocopherol transfer protein (α-TTP).
Hepatic α-TTP facilitates the selective incorporation of α-tocopherol into circulating lipoproteins that distribute the vitamin to nonhepatic tissues. α-TTP is therefore considered to be the major regulator of vitamin E status in humans
Humans with a deficiency of vitamin E display, among other symptoms, a mild anemia.
Persons with a chronic deficiency exhibit prolonged malabsorption of fats, as well as mild anemia, unsteadiness (ataxia), and pigmentary changes in the retina.
These symptoms respond to prolonged vitamin E treatment.
In experimental animals, the characteristic signs of induced vitamin E deficiency vary with the species.
Mature female rats with a deficiency of vitamin E fail to produce healthy young.
The vitamin deficiency in rabbits and guinea pigs is characterized mainly by muscle wasting.
Background
Vitamin E is the name given to a group of water-insoluble, plant-derived substances. There are eight naturally-occurring isomers and a number of semisynthetic or synthetic homologues. The naturally-occurring d- (or RRR) alpha-tocopherol is the most biologically active form and vitamin E activity is traditionally expressed in terms of equivalents of this isomer (mg alpha-tocopherol equivalents or a-TE). Other tocopherols such as gamma-tocopherol also have vitamin E activity. There are four tocopherol homologues (d-a-, d-ß-, d-?- and d-d-) and four tocotrienols. Other forms of vitamin E occur in lower amounts in foods and are less active in animal bioassay. The usual form in supplements is synthetic dl- (or all-rac) a-tocopherol that consists of a mixture of active and inactive stereoisomers, because natural vitamin E from wheat germ oil is expensive. The equivalence of the various forms is shown below:
Form
Alternative name
mg a-tocopherol equivalence
d-a-tocopherol
RRR-a-tocopherol
1
d-a-tocopherol acetate
RRR-a-tocopherol acetate
0.91
d-a-tocopherol acid succinate
RRR-a-tocopherol acid succinate
0.81
dl-a-tocopherol
all-rac-a-tocopherol
0.74
dl-a-tocopherol acetate
all-rac-a-tocopherol
0.67
d-ß-tocopherol
RRR-ß-tocopherol
0.25-0.40
d-?-tocopherol
RRR-?-tocopherol
0.10
a-tocotrienol
0.25-0.30
The major role of vitamin E is to protect polyunsaturated fatty acids (PUFA) from oxidation.
It acts as an anti-oxidant in the lipid phase of cell membranes. Vitamin E requirements have been reported to increase when intakes of PUFA are increased (Dam 1962, Horwitt 1962) and a ratio of at least 0.4 mg a-tocopherol per gram of PUFA has been recommended (Bieri & Evarts 1973, Horwitt 1974, Witting & Lee 1975). Most dietary sources of polyunsaturated fat are also relatively rich in vitamin E. However supplements of fish oils or other pure n-3 fatty acids may not provide the amount of vitamin E needed.
The activity vitamin E complements that of selenium-dependent glutathione peroxidase in protecting the membrane PUFAs from free radical damage.
Although vitamin E is mainly located in cells and organelle membranes, its concentration may be very low, suggesting that after its reaction with free radicals it is rapidly regenerated, possibly by other antioxidants such as selenium, ubiquinols and vitamin C (Doba et al 1985, Niki et al 1982, Stoyanovsky et al 1995).
The main source of vitamin E is fats and oils.
It is also found in some vegetables, in the fats of meat, poultry and fish and, to lesser degrees, in cereals and dairy foods.
About half the tocopherol in wheat germ, sunflower, safflower, canola, olive and cottonseed oils is a-tocopherol but soybean and corn oils contain about 10 times as much ?-tocopherol as a-tocopherol.
Most vitamin E is found in foods containing fat.
Absorption requires micelle formation and chylomicron secretion in the gut (Muller et al 1974) together with biliary and pancreatic secretions.
Efficiency of absorption is low, but the precise rate is unknown.
Vitamin E is transported in the blood by the plasma lipoproteins and erythrocytes.
Tocopherols are carried from the gut to the liver in chylomicrons where they are incorporated as chylomicron remnants.
Catabolism of chylomicrons takes place in the systemic circulation through the action of cellular lipoprotein lipase.
Vitamin E can be transferred to high density lipoprotein (HDL) and then to low density liopoprotein (LDL) and very low density lipoprotein (VLDL).
Most a-tocopherol enters peripheral tissues within the intact lipoprotein through the LDL receptor pathway.
Although all tocopherol homologues are absorbed similarly, a-tocopherol predominates in blood and tissue as the binding proteins take it up preferentially.
Plasma vitamin E and tissue concentrations vary little over a wide range of dietary intake and the brain is particularly resistant to depletion (Bourne & Clement 1991).
The main oxidation product of a-tocopherol is tocopheryl quinone which is conjugated to glucuronate and is excreted in bile or further degraded in the kidneys to a-tocopheronic acid before excretion in bile (Drevon 1991). Some may be excreted through the skin (Shiratori 1974).
Overt deficiency symptoms in normal individuals consuming diets low in vitamin E have never been described.
It occurs only as a result of genetic abnormalities, fat malabsorption syndrome (Rader & Brewer 1993, Sokol 1993) or protein-energy malnutrition (Kalra et al 1998, Laditan & Ette 1982). The main symptom is a peripheral neuropathy. Other symptoms include spinocerebellar ataxia, skeletal myopathy and pigmented retinopathy (Sokol 1988).
In epidemiological studies, higher intakes of vitamin E have been related to reduction in cardiovascular disease risk (Gey et al 1991, Rimm & Stampfer 1993, Stampfer et al 1993), diabetic complications (Baynes 1991, Mullarkey et al 1990, Semenkovich & Heinecke 1997), certain cancers (Comstock et al 1997, Eichhlozer et al 1996, Yong et al 1997) and cataracts (Jacques & Chylack 1991, Knekt et al 1992, Leske et al 1991).
Not all studies, however, have confirmed a relationship and clinical trials with supplements in high risk groups, have shown little benefit.
Further discussion of these trials is given in the ‘Chronic disease’ section.
Indicators that have been used to estimate vitamin E requirements include lipid peroxidation markers, oxidation products of DNA or proteins, vitamin E metabolite excretion, vitamin E biokinetics, vitamin E deficiency symptoms, plasma a-tocopherol concentration, hydrogen peroxide-induced haemolysis or the relationship of vitamin E to chronic disease status.
However, erythrocyte fragility studies have been the most widely used.
The recent US DRI review in 2000 used the data of Horwitt (1960, 1963).
These same data had been used in setting the earlier US RDIs but were interpreted differently in 2000, leading to considerably increased recommendations.
In the US DRI review of 2000, the amount of dietary vitamin E required to bring plasma a-tocopherol to a level where per cent haemolysis was low was used to estimate an EAR (Horwitt 1960, 1963).
However, the interpretation of these data is problematic in relation to level of plasma a-tocopherol at which adverse effects are seen, as there were no data available for plasma a-tocopherol concentrations between 5 and 12 µmol/L). All four subjects below 6 µmol/L plasma a-tocopherol (range 2-5 µmol/L) had haemolysis of about 80% or above and all 6 subjects with concentrations between 12 and 22 µmol/L), had haemodialysis of 12% or less.
There has been disagreement as to whether the ‘adequacy’ cut off should be midway between these two clusters or at the lowest point showing low haemolysis.
The data are dichotomous, not continuous, thus preventing an accurate dose-response analysis.
Changing the cut-off point makes a large difference to the estimated requirement.
In addition, the authors of the key paper themselves expressed concern about the validity of the technique for assessing vitamin E requirements (Horwitt 1960, 1963, 2001).
Vitamin E helps support the immune system, cell function, and skin health. It’s an antioxidant, making it effective at combating the effects of free radicals produced by the metabolism of food and toxins in the environment.
Vitamin E may be beneficial at reducing UV damage to skin.
It may also be effective at reducing the symptoms of atopic dermatitis and fatty liver disease, and for slowing the progression of mild to moderate Alzheimer’s disease.
Vitamin E is even used to widen blood vessels, reducing the risk of blood clots.
UV light and sun exposure reduce vitamin E levels in skin. Vitamin E levels also decrease with age. However, vitamin E is available in many foods, in supplement form, and as an ingredient in products applied topically.
What to know about vitamin E in foods
Vitamin E can be found in many foods, including:
certain commercially processed foods, such as cereal, juice, and margarine
abalone, salmon, and other seafood
broccoli, spinach, and other green vegetables
nuts and seeds, such as sunflower seeds, and hazelnuts
vegetable oils, including sunflower, wheat germ, and safflower oil
Natural vitamin E in food is often listed as d-alpha-tocopherol on food labels. Vitamin E is also produced synthetically.
The synthetic form of vitamin E is often referred to as dl-alpha-tocopherol.
Natural vitamin E is more potent than its synthetic version.
Vitamin E can be absorbed even better when combined with vitamin C.
Most people who live in areas where healthy food is available get enough vitamin E from food.
People with conditions that affect their ability to digest or absorb fat may need more vitamin E.
These conditions include cystic fibrosis and Crohn’s disease. For these people and others concerned about vitamin E intake, supplements may help.
Vitamin E is an ingredient in many multivitamin and mineral supplements.
Vitamin E oil can be used on your face as an overnight anti-aging treatment.
Since vitamin E has a thick consistency, it’s best to apply it before bed so that it can fully absorb.
If applied in the morning, you may have difficulty putting makeup or serums on top of it.
Typically, you can apply a serum or oil mixture containing vitamin E as an all-over treatment on your face.
This is different than using vitamin E to spot-treat a blemish, using a beauty treatment mask for a brief period of time, or taking an oral supplement that contains vitamin E.
Applying vitamin E as an anti-aging or skin-conditioning agent overnight involves letting the product completely absorb into your skin.
Most over-the-counter anti-aging creams contain between .05 and 1 percent vitamin E as one of their active ingredients.
Look for a product with a high concentration of vitamin E (alpha-tocopherol is often the ingredient name), or search for pure vitamin E oil.
TOPICAL VITAMIN E IN DERMATOLOGY
Topical vitamin E has emerged as a popular treatment for a number of skin disorders owing to its antioxidant properties.
It has been seen that reactive oxygen species have the ability to alter the biosynthesis of collagen and glycosaminoglycans in skin.
Most of the over-the-counter antiaging creams contain 0.5%–1% of vitamin E.
One of the most popular applications of vitamin E is the treatment of burns, surgical scars, and wounds.
However, studies looking at the efficacy of vitamin E in the treatment of burns and scars have been disappointing.
Topical vitamin E has also been found to be effective in granuloma annulare.
Vitamin E is one of the ingredients in over-the-counter treatments of skin aging.
Topical application of the gel containing 2% phytonadione, 0.1% retinol, 0.1% vitamin C, and 0.1% vitamin E has been seen to be fairly or moderately effective in reducing dark under-eye circles, especially in cases of hemostasis.
Antioxidants fight free radicals, which are electrons that have broken off from an atom.
Free radicals have been linked to a wide range of health conditions, from cancer to premature aging.
Vitamin E oil is derived from vitamin E and can be applied directly to the skin, or added to lotions, creams, and gels.
Vitamin E cannot treat allergic reactions, infections, and other issues that cause skin itching.
Because it moisturizes the skin, however, it may offer temporary relief from itching caused by dry skin.
Keeping skin well moisturised may help to prevent dry skin, and prevent symptoms such as itchiness.
Any kind of oil safe for skin may offer these benefits.
Eczema
Vitamin E may alleviate the dryness, itching, and flaking associated with eczema, or atopic dermatitis.
One studyTrusted Source found that oral vitamin E supplements could produce significant improvements in eczema symptoms.
Though vitamin E oil has not been well-studied in the treatment of eczema, it may increase the effectiveness of topical moisturizers.
Psoriasis
At least one studyTrusted Source has linked topical vitamin E to a reduction in psoriasis symptoms. Even better, the study showed that there were no serious side effects.
However, the effects of vitamin E on psoriasis were not as good as most readily available treatments. Vitamin E oil might be a good option for people who want to avoid prescription remedies and who have mild psoriasis.
Preventing or minimizing the appearance of scars
Folk wisdom has long suggested that vitamin E, applied to the skin, taken as a supplement, or both, might treat scars, or prevent them from forming in the first place.
But research does not support this claim and has found no association between vitamin E use and scar prevention.
In one older studyTrusted Source from 1999, almost one-third of participants had an allergic reaction to topical vitamin E, suggesting the oil is more likely to make scarring worse rather than prevent it.
A more recent literature reviewTrusted Source found that evidence about whether vitamin E improved or worsened scarring was inconclusive.
Research does suggest that well-moisturized skin is less likely to scar.
So for people who do not have an allergic reaction to vitamin E, using it as a moisturizer while the wound heals may offer some benefits.
Preventing or treating fine lines and wrinkles
Dry skin tends to look more wrinkled than well-moisturized skin. The moisturizing benefits of vitamin E oil may help the skin look more youthful and less wrinkled.
Claims that vitamin E prevents or treats wrinkles, however, are unsupported by scientific evidence.
The best strategy for preventing wrinkles is to avoid direct sunlight and to wear a quality sunscreen.
Benefits of Vitamin E Oil
A. Reduces Hyperpigmentation
Studies suggest that combining Vitamin E with Vitamin C can work as a natural sun protector and can reduce hyperpigmentation[2].
If you’re adventurous and enjoy staying out in the sun for long hours, this can be your new best friend!
B. Prevents Skin Aging
The antioxidants present in Vitamin E improves blood circulation. Vitamin E oil and other topical forms of Vitamin E slow down your skin-aging process [2].
The oil can make your skin look firm and youthful!
C. Improves Dry Skin Conditions
Vitamin E oil acts as a moisturizer to reduce and prevent dry skin. Studies suggest that Vitamin E oil can be helpful in treating mild psoriasis[3].
D. Removes Dirt
Vitamin E oil is a heavy emollient. It removes dirt from your pores to give you a refreshed and smooth appearance.
A few drops of Vitamin E oil should do the trick.
Vitamin E is an important fat‑soluble antioxidant and has been in use for more than 50 years in dermatology.
It is an important ingredient in many cosmetic products. It protects the skin from various deleterious effects due to solar radiation by acting as a free‑radical scavenger. Experimental studies suggest that vitamin E has antitumorigenic and photoprotective properties. There is a paucity of controlled clinical studies providing a rationale for well‑defined dosages and clinical indications of vitamin E usage in dermatological practice
The chemical term for Vitamin E is ‘Alpha-Tocopherol.’ It is a fat-soluble vitamin that acts as a powerful antioxidant, protecting cell membranes from the damage inflicted by free-radicals in the environment.
VITAMIN E is a vitamin that is being promoted for its ability to protect against aging of the skin caused by ultraviolet light, such as sunlight and to aid in the healing of minor burns and sunburns. These claims have not been evaluated by the FDA at this time.
Vitamin E is a naturally occurring vitamin that is found in many foods such as cereal grains, fruits, green leafy vegetables, vegetable oils, and wheat germ oil.
Vitamin E’s antioxidant properties are the most well-known and researched benefit.
It helps defend the skin against the negative effects of pollution and even has the ability to absorb UVB radiation (the sun’s short-length waves that cause burns).
When combined with Vitamin C, it’s been shown to be very effective in helping neutralize the free radical damage caused by UV rays, making it a beneficial addition to any sunscreen formulations.
Additionally, Vitamin E has been shown in some studies to provide a small amount of temporary relief to skin issues like eczema and psoriasis, and it has a long history of being used to help moisturize dry, irritated skin. It’s also an anti-inflammatory with calming properties.
While its antioxidant protection is one of its most well-known benefits, Vitamin E also has a long history of being used topically on skin that has been damaged or is irritated.
Its anti-inflammatory properties have been shown to provide some relief for UV-induced skin swelling, redness, roughness.
There is also some evidence of its ability to improve skin’s moisture-binding capacity to provide a moisturizing effect on the skin .
A longtime praised ingredient, vitamin E is a blanket term for a group of oil-soluble antioxidants (the most popular being tocopherol) and is found in many anti-aging serums and creams.
Vitamin E is an OG powerhouse that fights free radical damage, prevents fine lines and wrinkles, moisturizes the skin, and evens out skin tone.
Vitamin E is also a photoprotectant meaning it has natural capabilities to protect your skin against certain UV rays (PSA: it’s not a replacement for sunblock, but it will strengthen your sunscreen).
Vitamin E actually occurs naturally in the skin, but we lose these natural concentration levels as we age (bleh) making topical application critical for any anti-aging skin care regimen.
The one downside to vitamin E is this ingredient can trigger breakouts if you have acne prone skin and/or can cause irritation if you apply the product incorrectly.
If your skin reacts poorly to vitamin E, you can always eat foods rich in vitamin E (like avocados, almonds, sweet potatoes, sunflower seeds, whole grains, trout, olive oil, spinach, and more!) to capture some of the skin care benefits.
Vitamins, especially in daily nutrition, play an important role in our metabolism in general, as well as in skin’s metabolism.
Using vitamin E for healthy skin is pretty common knowledge, but not many people know exactly why.
Vitamin E is an antioxidant that neutralises free radicals while providing a level of protection against negative external influences like the sun’s harmful UV rays.
Free radicals damage collagen and cause skin dryness, fine lines and wrinkles.
They have also been the subject of extensive research and received a lot of media coverage in recent years.
By neutralising free radicals, antioxidants like vitamin E can help to prevent your cells from getting damaged.
Vitamin E is one of the most powerful antioxidants, but because our bodies can’t produce it, it’s important to ensure we are getting enough. Eating foods high in vitamin E can help to slow the skin’s anti-ageing process.
FOODS HIGH IN VITAMIN E INCLUDE
Nuts (especially almonds)
Vegetable oils (especially wheat germ oil)
Vegetables (especially sweet potato)
If you aren’t getting enough vitamin E from your diet, you can experiment with natural vitamin E supplements available from most health food stores and some supermarkets.
Before you try any supplements however, make sure to discuss your choices with a qualified health care professional.
Vitamin E is a well-loved ingredient for moisturizing skin, helping improve texture and softness.
As an antioxidant, Vitamin E helps protect the skin from damage from nasty free radicals—a big contributor to premature aging.
Found in some of our favorite foods like avocados, almonds, sweet potatoes and spinach, Vitamin E also helps prevent cell tissue damage by acting as a barrier for the skin.
Good to know
Vitamin E is a free radical-fighting antioxidant
Vitamin E helps minimize signs of premature aging
Vitamin E protects and helps prevent cell damage
Vitamin E is being marketed as one of the best anti-aging products available.
Vitamin E protects the skin’s cells from sun damage and pollution. It also helps the skin look younger by reducing the appearance of wrinkles.
It also helps in the treatment of some skin conditions.
Benefits of vitamin E in skincare
Vitamin E keeps our skin healthy by3:
Acting as an antioxidant
Boosting the immune system
Moisturising
Reducing signs of ageing
Antioxidant properties
Vitamin E protects the skin from the damaging effects of free radicals1. Free radicals are natural biological compounds formed when our bodies convert the food we eat into energy4. We are also exposed to free radicals in the environment from cigarette smoke, air pollution and ultraviolet light from the sun, all of which have damaging effects to the skin4.
The free radical molecules contain an unshared electron, making them highly energetic and react rapidly to form Reactive Oxygen Species (ROS)4. The ROS try to grab electrons from atoms in the skin, causing damage to skin’s DNA, which results in the ‘speeding up’ of the skin ageing process4,5.
Antioxidants help protect cells from these damaging effects and specifically vitamin E acts to neutralise the production of ROS when fat undergoes oxidation4.
Immune system boost
The body also uses vitamin E to boost its immune system to fight off invading bacteria and viruses. The vitamin E found in cellular membranes serves as a primary defence against potentially harmful oxidation reactions6. It also helps to widen blood vessels and keep blood from clotting within them4. This essential nutrient with anti-inflammatory properties helps to support the immune system and cell function as well as skin health.
Moisturising effect
Vitamin E is stored within the sebaceous glands of the skin which secrete an oily or waxy matter called sebum3. When applied topically, it boosts our levels of vitamin E within these glands, increasing sebum production which helps lubricate and waterproof our skin and hair3. It therefore acts as a useful moisturiser for dry skin areas such as cuticles and elbows3.
Anti-ageing effect
We all know that ultraviolet light from the sun damages our skin and speeds up the ageing process. UV light reduces vitamin E levels in the skin and creates free radicals and ROS, causing damage to the proteins and cells that form skin3.
Vitamin E levels also decrease with age3. By topically applying vitamin E, we can help boost our skin’s vitamin E levels and help protect skin from the damaging free radicals caused by sun exposure3.
So, vitamin E is a powerful antioxidant which when used topically can help nourish and protect skin from damaging free-radicals. Pretty radical.
VITAMIN E (ALPHA TOCOPHEROL)
WHY ADD VITAMIN E (ALPHA TOCOPHEROL) TO YOUR SKIN CARE ROUTINE?
The most abundant, pure form of vitamin E, this powerful antioxidant can be derived synthetically or sourced naturally from a variety of foods including vegetable oils. Alpha tocopheral plays an important role in neutralizing free radicals, moisturizing skin, and improving the appearance of visible skin aging.
Quick Facts
VITAMIN E is primary fat-soluble antioxidant in our skin
VITAMIN E shows significant photoprotection against UVB rays
Vit C + Vit E work in synergy and provide great photoprotection
VITAMIN E has emollient properties
VITAMIN E is easy to formulate, stable and relatively inexpensive
Vitamin E is the major fat-soluble antioxidant in our skin. As a strong antioxidant it’s an A-player in protecting the skin cells from the nasty little things called free-radicals that want to destroy the lovely collagen that makes our skin nice and firm.
Because it’s fat soluble our skin just loves to absorb it (as opposed to water soluble things where we have to trick our skin to absorb them).
Vit E can be found in many foods: vegetables, oils, seeds, nuts, corn, soy, whole wheat flour, margarine and even some meats and dairy products. The natural form is denoted by a ‘d’ in the beginning of the name and ‘dl’ denotes the synthetic form. While this is absolutely not always true, in this case research shows that the natural form is more active and is better absorbed.
The name tocopherol actually refers to a whole group of stuff and it has four subtypes: alpha, beta, gamma and delta. The subtypes are quite different: alpha-tocopherol is the nicest and most active one, while delta-tocopherol seems to be the lazy guy and does not even have antioxidant properties. In cosmetic products mixed tocopherol (containing all subtypes) or alpha-tocopherol is the best choice.
There are lots of studies showing that Vit E has some nice photoprotection properties, meaning it can protect the skin from UV (and in case of Vit E it’s mainly UVB) rays. If you put it on your skin, it lowers the production of sunburn cells, reduces the damage caused by UVB rays and inhibits photocarcinogenesis.
Tocopherols, the major forms of vitamin E, are a group of fat soluble phenolic compounds. Each tocopherol consists of chromanol ring and a 16-carbon phytyl chain
Tocopherol
From Wikipedia, the free encyclopedia
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Tocopherols (/toʊˈkɒfəˌrɒl/;[1] TCP) are a class of organic chemical compounds (more precisely, various methylated phenols), many of which have vitamin E activity. Because the vitamin activity was first identified in 1936 from a dietary fertility factor in rats, it was named “tocopherol”, from the Greek τόκος tókos ‘birth’ and φέρειν phérein ‘to bear or carry’, that is “to carry a pregnancy,” with the ending “-ol” signifying its status as a chemical alcohol.
α-Tocopherol is the main source found in supplements and in the European diet, where the main dietary sources are olive and sunflower oils,[2] while γ-tocopherol is the most common form in the American diet due to a higher intake of soybean and corn oil.[2][3]
Tocotrienols, which are related compounds, also have vitamin E activity. All of these various derivatives with vitamin activity may correctly be referred to as “vitamin E”. Tocopherols and tocotrienols are fat-soluble antioxidants but also seem to have many other functions in the body.
Contents
1 Forms
1.1 α-Tocopherol
1.2 Tocotrienols
2 Function and dietary recommendations
2.1 Mechanism of action
2.2 Dietary considerations
2.3 α-Tocopherol equivalents
3 Sources
4 Deficiency
5 Supplements
5.1 Synthetic all-racemic
5.2 Esters
5.3 Mixed tocopherols
6 Uses
6.1 Supplement popularity over time
6.2 Age-related macular degeneration
6.3 Complementary and alternative medicine
6.3.1 Antioxidant theory
6.4 Alzheimer’s disease
6.5 Cancer
6.6 Cataracts
6.7 Cardiovascular diseases
6.8 Pregnancy
6.9 Topical
7 Side effects
7.1 Drug interactions
8 Synthesis
9 History
10 See also
11 References
12 External links
Forms
Vitamin E exists in eight different forms, four tocopherols and four tocotrienols. All feature a chromane ring, with a hydroxyl group that can donate a hydrogen atom to reduce free radicals and a hydrophobic side chain that allows for penetration into biological membranes. Both the tocopherols and tocotrienols occur in α (alpha), β (beta), γ (gamma), and δ (delta) forms, determined by the number and position of methyl groups on the chromanol ring.
Form Structure
alpha-Tocopherol Tocopherol, alpha-.svg
beta-Tocopherol Beta-tocopherol.png
gamma-Tocopherol Gamma-tocopherol.png
delta-Tocopherol Delta-tocopherol.png
The tocotrienols have the same methyl structure at the ring and the same Greek letter-methyl-notation, but differ from the analogous tocopherols by the presence of three double bonds in the hydrophobic side chain. The unsaturation of the tails gives tocotrienols only a single stereoisomeric carbon (and thus two possible isomers per structural formula, one of which occurs naturally), whereas tocopherols have three centers (and eight possible stereoisomers per structural formula, again, only one of which occurs naturally).
Each form has a different biological activity.[4][5] In general, the unnatural l-isomers of tocotrienols lack almost all vitamin activity, and half of the possible 8 isomers of the tocopherols (those with 2S chirality at the ring-tail junction) also lack vitamin activity. Of the stereoisomers that retain activity, increasing methylation, especially full methylation to the alpha-form, increases vitamin activity. In tocopherols, this is due to the preference of the tocopherol binding protein for the alpha-tocopherol form of the vitamin.
As a food additive, tocopherol is labeled with these E numbers: E306 (tocopherol), E307 (α-tocopherol), E308 (γ-tocopherol), and E309 (δ-tocopherol). All of these are approved in the US,[6] EU,[7] and Australia and New Zealand[8] for use as antioxidants.
α-Tocopherol
Main article: alpha-Tocopherol
Alpha-tocopherol is the form of vitamin E that is preferentially absorbed and accumulated in humans.
The measurement of “vitamin E” activity in international units (IU) was based on fertility enhancement by the prevention of miscarriages in pregnant rats relative to alpha-tocopherol.
Although the mono-methylated form ddd-gamma-tocopherol is the most prevalent form of vitamin E in oils, there is evidence that rats can methylate this form to the preferred alpha-tocopherol, since several generations of rats retained alpha-tocopherol tissue levels, even when those generations were fed only gamma-tocopherol through their lives.
There are three stereocenters in alpha-tocopherol, so this is a chiral molecule.
The eight stereoisomers of alpha-tocopherol differ in the arrangement of groups around these stereocenters.
In the image of RRR-alpha-tocopherol below, all three stereocenters are in the R form. However, if the middle of the three stereocenters were changed (so the hydrogen was now pointing down and the methyl group pointing up), this would become the structure of RSR-alpha-tocopherol. These stereoisomers also may be named in an alternative older nomenclature, where the stereocenters are either in the d or l form.[11]
RRR stereoisomer of alpha-tocopherol, bonds around the stereocenters are shown as dashed lines (pointing down) or wedges (pointing up).
1 IU of tocopherol is defined as ⅔ milligrams of RRR-alpha-tocopherol (formerly named d-alpha-tocopherol or sometimes ddd-alpha-tocopherol).
IU is also defined as 1 milligram of an equal mix of the eight stereoisomers, which is a racemic mixture called all-rac-alpha-tocopheryl acetate.
This mix of stereoisomers is often called dl-alpha-tocopheryl acetate, even though it is more precisely dl,dl,dl-alpha-tocopheryl acetate).
However, 1 IU of this racemic mixture is not now considered equivalent to 1 IU of natural (RRR) α-tocopherol, and the Institute of Medicine and the USDA now convert IU’s of the racemic mixture to milligrams of equivalent RRR using 1 IU racemic mixture = 0.45 “milligrams α-tocopherol”.[12]
Tocotrienols
Tocotrienols, although less commonly known, also belong to the vitamin E family.
Tocotrienols have four natural 2′ d-isomers (they have a stereoisomeric carbon only at the 2′ ring-tail position). The four tocotrienols (in order of decreasing methylation: d-alpha, d-beta, d-gamma, and d-delta-tocotrienol) have structures corresponding to the four tocopherols, except with an unsaturated bond in each of the three isoprene units that form the hydrocarbon tail, whereas tocopherols have a saturated phytyl tail (the phytyl tail of tocopherols gives the possibility for 2 more stereoisomeric sites in these molecules that tocotrienols do not have). Tocotrienol has been subject to fewer clinical studies and seen less research as compared to tocopherol. However, there is growing interest in the health effects of these compounds.[13]
Function and dietary recommendations
Main article: Vitamin E
Tocopherols function by donating H atoms to radicals (X).
Mechanism of action
Tocopherols are radical scavengers, delivering an H atom to quench free radicals.
At 323 kJ/mol, the O-H bond in tocopherols is approximately 10% weaker than in most other phenols.
This weak bond allows the vitamin to donate a hydrogen atom to the peroxyl radical and other free radicals, minimizing their damaging effect.
The thus generated tocopheryl radical is relatively unreactive, but reverts to tocopherol by a redox reaction with a hydrogen donor such as vitamin C.
As they are fat-soluble, tocopherols are incorporated into cell membranes, which are protected from oxidative damage.
Dietary considerations
The U.S. Recommended Dietary Allowance (RDA) for adults is 15 mg/day.
The RDA is based on the alpha-tocopherol form because it is the most active form as originally tested.
Vitamin E supplements are absorbed best when taken with meals.
The U.S. Institute of Medicine has set an upper tolerable intake level (UL) for vitamin E at 1,000 mg (1,500 IU) per day.
The European Food Safety Authority sets UL at 300 mg alpha-tocopherol equivalents /day.
α-Tocopherol equivalents
For dietary purposes, vitamin E activity of vitamin E isomers is expressed as α-tocopherol equivalents (a-TEs).
One a-TE is defined by the biological activity of 1 mg (natural) d-alpha-Tocopherol in the resorption-gestation test.
According to listings by FAO and others beta-tocopherol should be multiplied by 0.5, gamma-tocopherol by 0.1, and a-tocotrienol by 0.3.
The IU is converted to aTE by multiplying it with 0.67.
These factors do not correlate with the antioxidant activity of vitamin E isomers, where tocotrienols show even much higher activity in vivo.
Sources
Main article: Vitamin E
The U.S. Department of Agriculture (USDA), Agricultural Research Services, maintains a food composition database.
In general, food sources with the highest concentrations of vitamin E are vegetable oils, followed by nuts and seeds.
Adjusting for typical portion sizes, however, for many people in the United States the most important sources of vitamin E include fortified breakfast cereals.
Deficiency
Main article: Vitamin E deficiency
Vitamin E deficiency is rare, and in almost all instances caused by an underlying disease rather than a diet low in vitamin E.
Vitamin E deficiency causes neurological problems due to poor nerve conduction.
These include neuromuscular problems such as spinocerebellar ataxia and myopathies
Deficiency also may cause anemia, due to oxidative damage to red blood cells.
Tocopherols are a family of compounds that together make up different forms of vitamin E. When you buy a supplement that’s advertised as “mixed tocopherols,” you’re purchasing a mixture of several different types of vitamin E.
There are eight naturally occurring forms of vitamin E, including four tocopherols: alpha-tocopherol, beta-tocopherol, gamma-tocopherol, and delta-tocopherol.
Each has a slightly different chemical structure.
These tocopherols often are combined in supplements with tocotrienols, similar vitamin E compounds that also come in alpha-, beta-, gamma-, and delta- forms.
Mixed tocopherols are found in oils (including olive oil, sunflower oil, and soybean oil), nuts, seeds, and in some leafy green vegetables, such as spinach.
Health Benefits
Vitamin E is a fat-soluble vitamin that serves as an antioxidant in your body, scavenging potentially harmful free radicals that can damage your cells.
Vitamin E plays a role in strengthening your immune system, preventing clogged arteries, and potentially in warding off cancer, helping to prevent eyesight loss, and even in preventing sunburns.
Alpha-tocopherol is the form of vitamin E that’s been studied the most and supplements advertised simply as “vitamin E” typically contain this form of the vitamin.
However, research suggests other forms of tocopherols have additional health benefits and getting a supplement with mixed tocopherols in recommended.
Tocopherols (vitamin E) are considered as the most important lipid soluble natural antioxidants, which prevent lipid peroxidation by scavenging radicals in membranes and lipoprotein particles, and, thus, they slow down the aging process
Tocopherol exists in four different forms designated as α, β, δ, and γ.
They present strong antioxidant activities, and it is determined as the major form of vitamin E.
Tocopherol, as a group, is composed of soluble phenolic compounds that consist of a chromanol ring and a 16-carbon phytyl chain.
The classification of the tocopherol molecules is designated depending on the number and position of the methyl substituent in the chromanol ring.
The different types of tocopherol can be presented trimethylated, dimethylated or methylated in the positions 5-, 7- and 8-. When the carbons at position 5- and 7- are not methylated, they can function as electrophilic centers that can trap reactive oxygen and nitrogen species.
Tocopherols can be found in the diet as part of vegetable oil such as corn, soybean, sesame, and cottonseed.
It is currently under the list of substances generally recognized as safe (GRAS) in the FDA for the use of human consumption
Tocopherol, or vitamin E, a fat-soluble vitamin is a naturally occuring antioxidant which can be isolated from vegetable oil.
When isolated Tocopherol, is a viscous oil that varies in color from yellow to brownish red. Rather than Tocopherol itself, esters of Tocopherol are often used in cosmetic and personal care products.
These esters include, Tocopheryl Acetate, the acetic acid ester of Tocopherol; Tocopheryl Linoleate, the linoleic acid ester of Tocopherol; Tocopheryl Linoleate/Oleate, a mixture of linoleic and oleic acid esters of Tocopherol; Tocopheryl Nicotinate, the nicotinic acid ester of Tocopherol; and Tocopheryl Succinate, the succinic acid ester of Tocopherol.
Potassium Ascorbyl Tocopheryl Phosphate, a salt of both vitamin E (Tocopherol) and vitamin C (Ascorbic Acid) may also be used in cosmetic products.
Other Tocopherol-derived ingredients that may be found in cosmetic products include Dioleyl Tocopheryl Methylsilanol, which is the dioleyl ether of Tocopheryl Acetate monoether with methylsilanetriol, and Tocophersolan, which is also called Tocopheryl Polyethylene Glycol 1000 Succinate.
The addition of succinic acid and an average of 22 ethylene oxide groups to Tocopheryl makes Tocophersolan a water-soluble form of Tocopherol.
In cosmetics and personal care products, Tocopherol and other ingredients made from Tocopherol, including Tocopherol esters are used in the formulation of lipstick, eye shadow, blushers, face powders and foundations, moisturizers, skin care products, bath soaps and detergents, hair conditioners, and many other products.
Why is it used in cosmetics and personal care products?
Tocopherol, Tocophersolan, Tocopheryl Acetate, Tocopheryl Linoleate, Tocopheryl Linoleate/Oleate, Tocopheryl Nicotinate, Tocopheryl Succinate, Dioleyl Tocopheryl Methylsilanol and Potassium Ascorbyl Tocopheryl Phosphate all function as antioxidants. Tocopherol, Tocopheryl Acetate, Tocopheryl Linoleate, Tocopheryl Linoleate/Oleate, Tocopheryl Nicotinate and Dioleyl Tocopheryl Methylsilanol also function as skin-conditioning agents – miscellaneous.
Synonyms Sources
Methyltocols ChemIDplus
tocoferol Español ChEBI
tocoferoles Español ChEBI
Tocopherol ChemIDplus
tocophérol Français ChEBI
tocopherols ChEBI
Tocopherols
Tocopherol [JP15] [Wiki]
α-tocopherol [Wiki]
(+)-a-Tocopherol
(+)-α-tocopherol
(2R)-2,5,7,8-tetramethyl-2-[(4R,8R)-4,8,12-trimethyltridecyl]-3,4-dihydro-2H-chromen-6-ol
(2R)-2,5,7,8-Tetramethyl-2-[(4R,8R)-4,8,12-trimethyltridecyl]-6-chromanol [ACD/IUPAC Name]
(2R)-2,5,7,8-Tetramethyl-2-[(4R,8R)-4,8,12-trimethyltridecyl]-6-chromanol [German] [ACD/IUPAC Name]
(2R)-2,5,7,8-Tétraméthyl-2-[(4R,8R)-4,8,12-triméthyltridécyl]-6-chromanol [French] [ACD/IUPAC Name]
(2R)-2,5,7,8-TETRAMETHYL-2-[(4R,8R)-4,8,12-TRIMETHYLTRIDECYL]CHROMAN-6-OL
(2R)-3,4-Dihydro-2,5,7,8-tetramethyl-2-((4R,8R)-4,8,12-trimethyltridecyl)-2H-1-benzopyran-6-ol
(2R)-3,4-Dihydro-2,5,7,8-tetramethyl-2-[(4R,8R)-4,8,12-trimethyltridecyl]-2H-1-benzopyran-6-ol
(2R,4’R,8’R)-2,5,7,8-Tetramethyl-2-(4′,8′,12′-trimethyltridecyl)-6-chromanol
(2R,4’R,8’R)-a-Tocopherol
(2R,4’R,8’R)-α-Tocopherol
(all-R)-a-Tocopherol
(all-R)-α-Tocopherol
(all-R)-α-Tocopherol
(R)-2,5,7,8-tetramethyl-2-((4R,8R)-4,8,12-trimethyltridecyl)-3,4-dihydro-2H-chromen-6-ol
(R,R,R)-a-Tocopherol
[2R-2R*(4R*,8R*)]-3,4-Dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-1-benzopyran-6-ol
2,5,7,8-Tetramethyl-2-(4′,8′,12′-trimethyltridecyl)-6-chromanol
215-798-8 [EINECS]
2H-1-Benzopyran-6-ol, 3,4-dihydro-2,5,7,8-tetramethyl-2-((4R,8R)-4,8,12-trimethyltridecyl)-, (2R)-
2H-1-Benzopyran-6-ol, 3,4-dihydro-2,5,7,8-tetramethyl-2-[(4R,8R)-4,8,12-trimethyltridecyl]-, (2R)- [ACD/Index Name]
5,7,8-trimethyltocol
59-02-9 [RN]
Almefrol
Antisterility vitamin
Aquasol E
a-Tocopherol
a-Tocopherol Acid
a-Tokoferol
covi-ox
Covitol
D-a tocopherol
Denamone
D-α tocopherol
D-α-Tocopherol
E Prolin
Emipherol
E-Mix 40
Endo E
Epsilan
Erevit forte
Esorb
Etamican
Etavit
Fujimix E 20N
Hydrovit E forte
Ilitia [Wiki]
Irganox E 201
Irganox E 217
Irganox E 218
Juvela E
Juvela Food 500
Juvela nicotinate [Trade name]
Lan-E
Med-E
MFCD00072045 [MDL number]
Palmvitee
Phytogermine
Profecundin
Renascin
Rhenogran Ronotec 50
Rocavit E
Rontex 201
Spavit E
Syntopherol
Tenox GT 1
Tokopharm
Vascuals
Verrol
Vi-E
Viprimol
Vitamin E [USP]
Vitamin E (DL-α-Tocopherol)
Vitamin E a
Vitamin E α
Vitaplex E
Vitayonon
VITEOLIN
Viterra E
α-tocopherol
α-Tocopherol
α-Tocopherol acid
α-Tokoferol
α-Tokoferol
a-D-Tocopherol
Phytogermin
RRR-α-tocopherol
RRR-α-tocopheryl
Vitamin Ea
α-δ-Tocopherol
δ-α-tocopherol
α-Tocopherol
&α;-tocopherol
((addition))-(α)-Tocopherol
(+)-α-tocopherol
(+)-α-Tocopherol
(±)-Med-E
(2R)-2-((4R,8R)-4,8,12-trimethyltridecyl)-2,5,7,8-tetramethylchroman-6-ol
(2R)-2,5,7,8-tetramethyl-2-[(4R,8R)-4,8,12-trimethyltridecyl]-3,4-dihydro-2H-1-benzopyran-6-ol
(2R)-2,5,7,8-tetramethyl-2-[(4R,8R)-4,8,12-trimethyltridecyl]-3,4-dihydrochromen-6-ol
(2R*(4R*,8R*))-(1)-3,4-Dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-benzopyran-6-ol
(2R,4’R,8’R)-α-tocopherol
(R)-2,5,7,8-Tetramethyl-2-((4R,8R)-4,8,12-trimethyltridecyl)chroman-6-ol
(R,R,R)-α-tocopherol
(R,R,R)-α-tocopherol
[2R-[2R*(4R*,8R*)]]-3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-1-benzopyran-6-yl nicotinate
113892-08-3 [RN]
1406-66-2 [RN]
18920-62-2 [RN]
2,5,7,8-Tetramethyl-2-(4′,8′,12′-trimethyltridecyl)-6-chromanol
21-59-0 [RN]
3,4-Dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-benzopyran-6-ol
5-17-04-00168 [Beilstein]
5300493 [Beilstein]
6-Chromanol, 2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-
94012 [Beilstein]
Amino-Opti-E
a-Vitamin E
D-&α
d-a-tocopherol
d-α-tocopherol
Ephanyl
Eprolin [Trade name]
http://www.hmdb.ca/metabolites/HMDB0001893
https://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:18145
α-Tocopherol-d6
ido-E
MFCD00006848 [MDL number]
MFCD00072051 [MDL number]
Pheryl-E
Vita plus E
VitaE
Vitamin-E [Trade name]
VIV
α Tocopherol
α -Tocopherol
α-TOCOPHEROL, D-
α-Vitamin E
Vitamin antioxidants are used to stabilize oxygen- sensitive ingredients in cosmetic formulations. DL-α-Tocopherol protects formulation against oxidation.
Tocopherols are a series of chiral organic molecules that vary in their degree of methylation of the phenol moiety of the chromanol ring. Tocopherols are lipid soluble anti-oxidants that protect cell membranes from oxidative damage. α-Tocopherol is the form of tocopherol preferentially absorbed by humans.