Vitamin E supplement benefit, side effects, natural versus synthetic, dosage, food sources,Information by Ray Sahelian, M.D.
September 20 2016

Also known as tocopherol, it was isolated in the 1920s. There is general agreement that this fat soluble oil can function as an excellent antioxidant protecting cells from damage. The discovery of vitamins was a major scientific achievement in our understanding of health and disease. In 1912, Casimir Funk originally coined the term vitamine. The major period of discovery began in the early nineteenth century and ended at the mid-twentieth century.

Vitamin E (α-tocopherol) was discovered nearly 100 years ago because it was required to prevent fetal resorption in pregnant, vitamin E-deficient rats fed lard-containing diets that were easily oxidizable. The human diet contains eight different vitamin E-related molecules synthesized by plants; despite the fact that all of these molecules are peroxyl radical scavengers, the human body prefers α-tocopherol. The biological activity of vitamin E is highly dependent upon regulatory mechanisms that serve to retain α-tocopherol and excrete the non-α-tocopherol forms. This preference is dependent upon the combination of the function of α-tocopherol transfer protein (α-TTP) to enrich the plasma with α-tocopherol and the metabolism of non-α-tocopherols. α-TTP is critical for human health because mutations in this protein lead to severe vitamin E deficiency characterized by neurologic abnormalities, especially ataxia and eventually death if vitamin E is not provided in large quantities to overcome the lack of α-TTP. α-Tocopherol serves as a peroxyl radical scavenger that protects polyunsaturated fatty acids in membranes and lipoproteins. Although specific pathways and specific molecular targets have been sought in a variety of studies, the most likely explanation as to why humans require vitamin E is that it is a fat-soluble antioxidant.

Synthetic vitamin E versus natural, is there a difference?
On a supplement label natural vitamin E is listed as d-alpha tocopherol. In contrast, synthetic forms of vitamin E are labeled with a dl- prefix, dl-alpha-tocopherol. Many studies evaluating the role of vitamin E in health and disease have focused mostly on synthetic vitamin E supplements without the investigators recognizing that health benefits could be different between the two. Also, some researchers do not recognize the likelihood that several types of vitamin E substances are beneficial, not just alpha tocopherol.

Types of natural vitamin E supplements
Several types are available, including alpha, beta, gamma and delta tocopherol. Alpha-tocopherol seems to be the most active, although we should not dismiss the importance of the others. It seems prudent to supplement with natural vitamin E products that have mixed tocopherols as opposed to just alpha tocopherol. Tocotrienols and
tocopherols are potent antioxidants that are 100% natural.

MultiVit Rx High Quality Daily Vitamins and Minerals with natural vitamin E complex

MultiVit Rx product has 100 units of natural vitamin E complex of mixed tocopherols per serving.

Why take a combination of tocopherols?
Supplementation with alpha-tocopherol reduces serum concentrations of gamma- and delta-tocopherol. Therefore, it appears that it is healthier to take a combination of different natural forms of vitamin E.

Deficiency in the American diet
Adv Nutr. 2014. Vitamin E inadequacy in humans: causes and consequences. It is estimated that more than 90% of Americans do not consume sufficient dietary vitamin E, as α-tocopherol, to meet estimated average requirements.

Benefit of Vitamin E - synthetic or natural
The benefits are often debated in the medical community.  Much of the confusion is due to the fact that researchers have used and analyzed different forms and different dosages. For instance, much of the research regarding the benefit has been done with synthetic vitamin E, specifically dl-alpha tocopherol as opposed to natural alpha tocopherol. Making this even more complicated, researchers have rarely analyzed the benefit of a natural vitamin E complex that includes a mix of tocopherols and tocotrienols. Hence, when you read a study that comments on the benefits and risks of vitamin E supplementation, always look to see what form they are talking about.

Aging and anti-aging
Taking a high dose of vitamin E routinely does not increase your chances of living longer, and in fact it seems to have a negative effect. Vitamin E supplementation at doses higher than 400 International Units (IU) per day apparently raises all-cause mortality rates and should be avoided. Because of its antioxidant properties, vitamin E supplementation has been studied in many trials to prevent chronic diseases. Several of those studies have hinted at increased mortality rates, but the number of participants in the each study was too small to tell if the results were real or occurred by chance. Dr. Edgar R. Miller III, at Johns Hopkins Medical Institutions in Baltimore, pooled data from 19 trials. These included nearly 136,000 subjects who were randomly assigned to take vitamin E or placebo capsules and were followed for more than a year. Overall, vitamin E supplementation did not affect mortality rates. However, the 11 trials testing doses of 400 IU daily or higher showed 39 more deaths occurred per 10,000 people taking high-dose vitamin E than among the same number of people taking a placebo. For low doses of vitamin E -- less than 150 IU daily -- all-cause mortality rates were slightly decreased, although this difference was not significant from a statistical standpoint. When the researchers factored in the simultaneous use of other vitamins or minerals, the reduction in the risk of dying with low-dosage vitamin E was toned down, but the risk at higher doses was increased. Annals of Internal Medicine, November 10 online, 2004.
     Dr. Sahelian says: I always thought that, for most people, taking more than 100 to 200 units a day of vitamin E was not necessary. The one problem with this study, though, is that it probably did not make a distinction between synthetic vitamin E supplements and natural vitamin E.
Also, the study did not account for the d-alpha form of vitamin E versus a natural Vitamin E supplement that includes all the tocopherols and tocotrienols. Even though it is a flawed study, I still think 30 to 200 units of vitamin E a few times a week is acceptable and perhaps beneficial.

Alzheimer's disease
Dec. 31, 2013, Journal of the American Medical Association - A large daily dose, 2,000 units a day for a period of 2 years, might help slow progression of the memory-robbing illness. However, when used for decades, the dose should be no more than 100 units a day, and I suggest using a mixed tocopherol product.

May 2009 - Dr. Alireza Atri at Massachusetts General Hospital, the VA Bedford Medical Center, and Harvard Medical School, Boston, led a National Institutes of Health-sponsored research. Patients were given standard-of-care treatment with a drug intended to help with Alzheimer's. As part of their clinical care, 208 patients also took vitamin E but no anti-inflammatory meds, 49 took an anti-inflammatory med but no vitamin E, 177 took both vitamin E and an anti-inflammatory med, and 106 took neither. While the daily dose of vitamin E ranged from 200 to 2000 units, the majority of patients were given high doses that ranged from 800 units daily to 1000 units twice daily. After an average of 3 years, there was a modest slowing of decline in function in those taking vitamin E. Dr. Alireza Atri reports taking an anti-inflammatory medication was associated with only a small effect on slowing long-term decline in cognitive functioning. In patients who took both vitamin E and anti-inflammatory medications, there appeared to be an additive effect in terms of slowing overall decline.

Relation of the tocopherol forms to incident Alzheimer disease and to cognitive change.
American Journal of Clinical Nutrition, 2005
High intake of vitamin E from food (tocopherol), but not from supplements (which usually contain -tocopherol), is inversely associated with Alzheimer disease. We examined whether food intakes of vitamin E, -tocopherol equivalents (a measure of the relative biologic activity of tocopherols and tocotrienols), or individual tocopherols would protect against incident Alzheimer disease and cognitive decline over 6 y in participants of the Chicago Health and Aging Project. Design: The 1993–2002 study of community residents aged 65 y included the administration of 4 cognitive tests and clinical evaluations for Alzheimer disease. Higher intakes of vitamin E and -tocopherol equivalents were associated with a reduced incidence of Alzheimer disease in separate multiple-adjusted models that included intakes of saturated and trans fats and docosahexaenoic acid. - and -Tocopherol had independent associations. In separate mixed models, a slower rate of cognitive decline was associated with intakes of vitamin E, -tocopherol equivalents, and - and -tocopherols. The results suggest that various tocopherol forms rather than - tocopherol alone may be important in the vitamin E protective association with Alzheimer disease.

Amyotrophic lateral sclerosis (ALS)
Regular users of vitamin E are at decreased risk for death from Lou Gehrig's disease, also called amyotrophic lateral sclerosis (ALS), compared with nonusers. Given that vitamin E is an antioxidant, the findings support the hypothesis that oxidants play a key role in the development of ALS. Still, use of another antioxidant, vitamin C, seemed to confer no protection against ALS, the report in the Annals of Neurology indicates. In the study, Dr. Alberto Ascherio, from Harvard School of Public Health in Boston, and colleagues analyzed data from nearly 1 million subjects enrolled in the American Cancer Society Cancer Prevention Study II. All of the subjects were at least 30 years of age when the study began in 1982. Compared with nonusers, patients who took vitamin E for less than 15 days per month did not reduce the risk of death from ALS. However, patients who used vitamin E for 15 or more days per month for at least 10 years had a reduced risk of ALS death. Vitamin C is "a water-soluble antioxidant with different properties than vitamin E and thus may not" act the same in the body. Annals of Neurology, 2004.

I am 26 years old and just wanted to check can i start using vitamin E supplements or will it create any problem in future. I even wanted to confirm whether intake of this and other antioxidants is beneficial or harmful.
   This is too broad a question and difficult to answer since each person has a different diet, requirement, and there are many types of vitamin E supplements and other vitamin products and antioxidants on the market with different dosages.

Additional antioxidants that could be taken with vitamin E:
Aceytylcysteine is a potent antioxidant used to protect the liver from acetaminophen toxicity.
Acetyl l Carnitine is an antioxidant and a mental stimulant.
Carnosine is an antioxidant and improves energy levels.
Curcumin is a spice that has become very popular over the past few years.
Lipoic acid is often used by those with diabetes.

Vitamin E and cataracts
A study from Sweden indicates that it can protect against cataracts caused by ultraviolet radiation in laboratory rats. The study exposed two groups of rats to ultraviolet light and found that the group given vitamin E developed only slight opacities while the group deprived of it developed cataracts. Human studies have not shown consistent results.

Vitamin E and cancer prevention or treatment
Its role in cancer is a hotly debated topic, and you can find viewpoints on both ends of the spectrum, each quoting their own facts and studies. Some researchers feel supplementation could reduce the risk of certain cancers, while others disagree. There have been many studies on this topic, yet no firm conclusions can be made regarding their role cancer prevention. Part of the problem lies in calculating or determining the ideal vitamin E dosage, and also the form of vitamin E, whether natural or synthetic. I think low dosages are helpful whereas too much can be counterproductive.

Taking high-dose vitamin E supplements for an extended period doesn't protect against cancer; in fact, it may even speed up the development of latent cancers. Researchers from Hotel-Dieu de Quebec Research Centre and Universite Laval published their results in the Journal of the National Cancer Institute. Dr. Isabelle Bairati, professor at the Universite Laval Faculty of Medicine and researcher at Hotel-Dieu de Quebec's Oncology Research Centre, conducted the study among 540 volunteers over an eight-year period. All the participants were treated for early stage head and neck cancer and were at high risk of developing another cancer. During the first three years, half of the participants received 400 international units of vitamin E daily, while the rest were given a placebo. In the three years during which participants were given either vitamin E supplements or a placebo, researchers recorded more cancer cases in the vitamin E group than in the placebo group. In the period after the supplements were stopped, the situation was reversed: more cancer cases were recorded in the placebo group than in the vitamin E group. At the end of the eight-year period, the percentage of patients who developed cancer was the same in both groups (30%). - Researchers suggest that the use of vitamin E supplements may have sped up the development of latent cancers in the patients who were part of the vitamin E group. "This cancer chemoprevention trial was conducted in a population of patients at high risk of second cancers. There is some concern about the generalization of the study results to individuals in the general population who are at low risk of a first cancer. Nevertheless, our results suggest that caution should be advised regarding the use of high-dose vitamin E supplements for cancer prevention," explained Dr. Isabelle Bairati.
   Dr. Sahelian comments: I wish the researchers had used a lower amount, such as 100 units -- and in the natural, mixed form. Perhaps the results would have been much different.

A daily dose of vitamin E may help delay the onset of type 2 diabetes in people at high risk of the disease. Researchers in New Zealand found that high-dose vitamin E appeared to temporarily improve insulin resistance -- a precursor to type 2 diabetes -- among 41 overweight adults. Though the improvement was short-lived, another diabetes risk factor -- elevations in a liver enzyme called alanine transferase -- changed for the better throughout the six-month study. Some past studies have reached similar conclusions. A recent study found that people whose diets had a healthy dose of antioxidants, including vitamin E, had a lower diabetes risk than those with lower antioxidant intakes.

Heart disease
The role of vitamin E in heart disease is another hotly debated topic in the medical community, and again you can find viewpoints on both ends of the spectrum,. Over the years there have been several studies on the role of vitamin E in heart disease, with some studies indicating that it could be helpful, whereas other results have not been as promising. Part of the problem lies in calculating or determining the ideal dosage, and the form.

Menstrual cramps
Women may find some relief from menstrual cramps by taking vitamin E a few days a month. A study of teenage girls in Iran found that those who took it starting two days before their periods suffered less cramping than their peers who used only standard pain medication according to Dr. Saeideh Ziaei and her colleagues at Tarbiat Modarres University in Tehran. Common menstrual cramps, or primary dysmenorrhea, are thought to result from the release of hormone-like substances called prostaglandins which cause the uterus to contract in order to expel the uterine lining, resulting in menstrual blood flow. Vitamin E, by acting on two enzymes in the body, can inhibit the formation of prostaglandins -- and, potentially, menstrual cramps. Girls in the vitamin E group took 200 milligrams (mg) of the vitamin twice a day, starting two days before they expected their periods and continuing through the third day of menstruation. Both groups were allowed to take ibuprofen if they needed to. British Journal of Gynecology, April 2005.

Parkinson's disease
There may a potential for this nutrient to be of benefit in Parkinson's disease.

Vitamin E and pregnancy
Women who've just become pregnant should be careful with their usage. It seems that high levels early in pregnancy may increase the risk of the baby being born with a heart defect. High levels may cause an imbalance in the oxidant / antioxidant state in embryonic tissues. Other possible mechanisms for the adverse effects of high vitamin E on the baby include modification of genes involved in embryonic heart development and inhibition of cellular enzymes involved in clearing away naturally occurring toxins. International Journal of Obstetrics and Gynaecology, 2009.

Prostate cancer
What is your take on vitamin E and prostate cancer? Do you advise discontinuing it's use? I read a study that followed up on men who took high doses, 400 mg, of the vitamin daily for about five years found they had a slightly increased risk of prostate cancer — even after they quit taking the pills.
   A. I am not a big proponent of high dose intake and don't think people should take more than 100 units of vitamin E a day. However, this study had two major flaws. One was the fact that the dosages of vitamin E given to patients was very high at 400 units a day, and second it was in a synthetic form as all rac-α-tocopheryl acetate as opposed to a vitamin E complex that includes a variety of several natural forms of tocopherols and tocotrienols.

High blood levels of alpha- and gamma-tocopherol, seem to cut the risk of prostate cancer by about 50 percent each. The findings are based on an analysis of 100 individuals with prostate cancer and 200 cancer-free "controls" participating in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study, which included nearly 30,000 Finnish men. Men with the highest levels of alpha-tocopherol in their blood at baseline were 51 percent less likely to develop prostate cancer than those with the lowest levels. Similarly, men with the highest levels of gamma-tocopherol were 43 percent less likely to develop the disease compared with men with the lowest levels. Further analysis showed that the link between high tocopherol levels and low cancer risk was stronger among subjects using alpha-tocopherol supplements than among non-users. This supports the original findings from the ATBC study, which showed that daily vitamin E supplementation reduced the risk of prostate cancer. Journal of the National Cancer Institute, March 2, 2005.

Vitamin E and scar formation, skin health
Some people think they break out with acne or pimples if they use vitamin E oil or vitamin E cream or vitamin E gel on their face.

The effects of topical vitamin E on the cosmetic appearance of scars.
Dermatol Surg. 1999. Baumann LS, Spencer J. University of Miami Department of Dermatology and Cutaneous Surgery, Miami, Florida
Anecdotal reports claim that vitamin E speeds wound healing and improves the cosmetic outcome of burns and other wounds. Our study shows that there is no benefit to the cosmetic outcome of scars by applying vitamin E after skin surgery and that the application of topical vitamin E may actually be detrimental to the cosmetic appearance of a scar.

Vitamin E side effects, safety, caution, danger
Very high dosages, such as 1,000 units or more, can lead to an increase in bleeding tendency, tiredness, weakness, headache, nausea, and possibly impaired immune function. The benefit probably diminishes after a dosage of 200 units and side effects start after 1000 units. The side effects go away relatively quickly after stopping the supplement. It is nearly impossible to become vitamin E toxic from food alone. An infrequent vitamin E side effect is allergy which may be in the form of breathing difficulty and swelling of the lips, tongue or face.
As with any supplement, overdosage or taking too much vitamin E is quite possible. Overdosage  or toxicity with vitamin E can lead to gastrointestinal disturbances, but I have not heard of fatalities or any major and immediate danger from taking too many vitamin E supplement pills.

The average American diet contains between 10 and 22 international units of vitamin E. Additional intake may be beneficial. Most healthy adults should do well with supplementing with 20 to 200 units of natural vitamin E complex two or three times a week. I do not recommend daily doses above 400 units. Since vitamin E is fat soluble, it need not be taken daily. Avoid synthetic vitamin E supplements.

I am a nutritionist practicing in Chicago and came across an editorial in the American Journal of Clinical Nutrition by Maret G Traber who is at the Linus Pauling Institute at Oregon State University in Corvallis, OR. Here is the last paragraph of the editorial: "And so we are left with the good news that the serum concentration of {alpha} - tocopherol is associated with decreased chronic disease risk, but we still do not know how much vitamin E to recommend for consumption to achieve that concentration. It may be that large vitamin E supplements are not necessary to achieve optimal serum {alpha} - tocopherol concentrations, in that the recommended dietary allowance of 15 mg per day may yield optimal serum concentrations to achieve significant reductions in chronic disease mortality. However, 15 mg a day may be an intake that is achieved only with supplements, given the dietary habits of most Americans and the observation that vitamin E–rich food sources are less popular foods, such as nuts, seeds, and vegetable oils, including olive, sunflower, or safflower oils.
   A person's optimal vitamin E supplement requirement is influenced by many factors, particularly diet. I think a vitamin E supplement intake of 20 or 30 to 200 units a couple of times a week is reasonable, and frankly I don't see the need to take megadoses beyond 200 to 400 units a day.

Food sources
The food content of vitamin E is well known. Foods high in vitamin E most commonly include wheat germ oil, almonds, sunflower seeds, whole grains, wheat germ, spinach, and a number of oils.

Vitamin E Research
Vitamin E and respiratory tract infections in elderly nursing home residents: a randomized controlled trial.
JAMA. 2004.
Vitamin E supplementation has been shown to improve immune response in elderly persons especially if they have a deficiency. To determine the effect of 1 year of vitamin E supplementation on respiratory tract infections in elderly nursing home residents. A randomized, double-blind, placebo-controlled trial was conducted at 33 long-term care facilities in the Boston, Mass, area. A total of 617 persons aged at least 65 years and who met the study's eligibility criteria were enrolled. Vitamin E (200 IU) or placebo capsule administered daily; all participants received a capsule containing half the recommended daily allowance of essential vitamins and minerals. Supplementation with 200 IU per day did not have a statistically significant effect on lower respiratory tract infections in elderly nursing home residents. However, we observed a protective effect of vitamin E supplementation on upper respiratory tract infections, particularly the common cold, that merits further investigation.

Vitamin E and CoQ10 work well together for heart and circulation
One of the early signs of vascular disease is inflammation within the walls of the arteries. This inflammation attracts white blood cells and other types of cells floating in the blood to the damaged inner lining of the arteries, resulting in plaque formation and increased likelihood of clotting. The initial inflammation and subsequent damage can result from a number of factors, including oxidation or free radical damage, high cholesterol, and high homocysteine.
     Researchers gave 21 baboons a high fat, high-cholesterol diet (just like my Thanksgiving meal) daily for 7 weeks and measured the blood level of a substance you will hear of more in the future called CRP, short for C-reactive protein. CRP is a marker for inflammation. The higher the CRP, the more damage to the inner lining of a blood vessel, like the coronary arteries in the heart. At the end of the 7 weeks, they continued with this high fat, high cholesterol diet, but this time they added vitamin E. The addition of vitamin E reduced the level of CRP. Then they added COQ10 on top of the vitamin E for another 2 weeks. They discovered that the levels of CRP dropped even further. The researchers conclude, "Dietary supplementation with vitamin E alone reduces the baseline inflammatory status that is indicated by the CRP concentration in healthy adult baboons. Co-supplementation with CoQ10 significantly enhances this effect of vitamin E."
     Dr. Sahelian says: For those of you with a heart condition or high cholesterol, or a family history of heart disease, it would make sense to take vitamin E complex and CoQ10. Discuss with your doctor if these are appropriate for your condition. A reasonable amount would be 30 to 200 units daily of natural vitamin E complex, or 100 to 300 units two or three times a week since vitamin E is fat soluble and can be stored in fat cells. As to CoQ10, a range of 20 to 60 mg is appropriate, a few times a week. CoQ10 is also fat soluble and is best taken with breakfast. Vitamin E can be taken with any meal.

Q. What is vitamin E oil used for?
   A. I don't have a good understanding of vitamin E oil at this time and don't have a good idea what benefit vitamin E oil can have.

Q. Hi Dr. Sahelian, How are you? I hope all is well. I'm hoping you could help me for an article I'm writing on anti-aging antioxidants for Remedies magazine. I'm looking for someone to comment on vitamin E. Since there is so much information (and misinformation) out there, I was wondering if you could just offer a comment or two on your stance on vitamin E. Does it work/not work, is it safe/unsafe? What role, if any, does it play in anti-aging? I'd appreciate any help you could give me.
   A. There is no proof as of now, that supplementing with vitamin E has anti-aging benefits, but most of the research points to the possibility that vitamin E supplements could have health improving benefits, and maybe reduce the risk of heart disease and cancer. The ideal dosage and frequency of intake is currently not known. Research does point to the fact that high doses may be counterproductive. If someone were to supplement with vitamin E, daily amounts should be less than 200 units, and it is highly recommended that vitamin E be natural and include most of the different forms of vitamin E, such as alpha, delta, gamma tocopherols, etc since in foods we find many different forms. In my opinion, some of the research with vitamin E has been flawed since scientists often evaluated supplementation with only the alpha form, and excluded the rest. In addition, the research sometimes focused on the synthetic form of vitamin E, known as dl-alpha-tocopherol, as opposed to the natural form, d-alpha-tocopherol. The outcomes may have been different if natural forms of vitamin E were used rather than synthetic.

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Q. I recently came across your website and very much appreciate your very objective and thoughtful commentary and recommendations. My question is this: Is it possible to determine how much vitamin E is contained in any particular softgel, given that the vitamin E d-alpha tocopherol component is always given in IU but the gamma and other mixed tocopherols and tocotrienols are given only in milligrams. I realize you can't apply the same conversion formula, but is there some way to figure out approximately how much total vitamin E one is getting in a given capsule? By way of context, my husband's severe short term memory loss has not benefited from taking Aricept and Namenda. Having read that high gamma vitmain E might have special benefits, I purchased some Life Extension Gamma E Tocopheral / Tocotrienols full spectrum Vitamin E, whose gelcaps contain 46 IU of D-alpha tocopherol and 325 mg of gamma E mixed tocopherols (mainly gamma), plus 145 mg of tocotrienol complex. Since my husband takes warfarin for his long standing lone atrial fibrillation (benign AF with no underlying heart disease), I didn't want to exceed 400 daily IU of vitamin E. When I called the company to ask how I could determine approximately how much total vitamin E there was in one of the Life Extension softgels, I was told I could get an approximation of the total IU by multiplying the milligrams of gamma E mixed tocopherols and the totcotrienols by 1.49 and adding this to the 46 IU of D-alpha tocopheral. If this is correct, one capsule would contain 746 IU-- far more than 400 IU/day. However I later came across your excellent website and you list a Now Foods Tocopherol Complex Vitamin E supplement, and under Amount Per Serving, it says 15 mg of Gamma tocopherol equals 2.9 IU-- or 0.19 IU per milligram. And obviously there is a huge discrepancy between 0.19 IU and 1.49 IU per milligram.
I realize you can't comment on what dosage or what particular composition of vitamin E might be appropriate in my husband's case, but could you possibly comment on the above discrepancy. And since others may be as confused as I, could you indicate how one could determine approximately how much total vitamin E one is getting in a given supplement, when the d-alpha tocopherol is given in IU but the other components are given only in milligrams?
   A. These are good questions. The exact potencies of different tocopherols and tocotrienols as related to alpha tocopherol are difficult to find and different research labs have come up with different numbers, but I came across one source that appears to be reliable. It appears that one mg of alpha tocopherol is equal to one iu of alpha tocopherol. The United States Department of Agriculture conversion factors as reported by McLaughlin and Weihrauch are:
alpha-tocopherol = 1.00
beta-tocopherol = 0.40
gamma-tocopherol = 0.10
delta-tocopherol = 0.01
alpha-tocotrienol = 0.30
beta-tocotrienol = 0.05
gamma-tocotrienol = 0.01
   Another source has conversion factors cited by McCance and Widdowson. the vitamin E values are:
alpha-tocopherol = 1.00
beta-tocopherol = 0.30
gamma-tocopherol = 0.15
alpha-tocotrienol = 0.30
   Therefore it appears that 1 mg of gamma tocopherol has similar potencies to about 0.1 mg to 0.15 mg or 0.1 to 0.15 iu of vitamin E alpha tocopherol.
   Having said all this, it is important not to get bogged down in details and lose sight of the overall picture. As a general rule it may not be a good idea to consume more than 100 or 200 units of vitamin E a day. Therefore, if a person is taking a supplement that has several hundred milligrams of vitamin E, one option is to only take it a couple of times a week. Vitamin E is fat soluble and can stay in tissues. Also, even though gamma tocopherol may be less potent than alpha tocopherol, it may play a different role in the body that could make it useful in ways that alpha tocopherol is not able to. In addition, vitamin E studies have not shown consistent results in terms of effectiveness as a treatment for short term memory loss.

Buy Natural Vitamin E supplement - Tocopherol Complex supplement, 60 softgels, Now Foods

Buy Vitamin E 100 iu

Supplement Facts
Serving Size: 1 Softgel
  Amount Per Serving %DV
Vitamin E (as d-Alpha Tocopherol plus d-Beta, d-Delta and d-Gamma Tocopherols)

Use: As a dietary supplement, take one vitamin E softgel a few times a week with food. Since it is fat soluble and is stored if fat tissue in the body, it need not be taken every day. The RDA for vitamin E is about 15 units per day. It's quite possible that higher amounts could be more beneficial.

Products also available to buy online
Jarrow Formulas, Famil-E, 60 Softgels