It is important to know that there are several types of Vitamin E. Vitamin E is actually a generic name for eight separate compounds. Some members of the vitamin E family are called tocopherols. These members include alpha tocopherol, beta tocopherol, gamma tocopherol, and delta tocopherol. Other members of the vitamin E family are called tocotrienols. These members include alpha, beta, gamma, and delta tocotrienol. Both groups all blended together in plants and animals, which is why the best form of vitamin E comes from your food.
The first research on vitamin E carried out by the Shute brothers early in the 19th century, showed that in rats, one part of vitamin E, alpha tocopherol, appeared more potent since it was necessary for successful pregnancy and production of offspring. For this reason, the Shutes named the vitamin "tocopherol," from the Greek word meaning "to give birth."
Nearly all of the clinical research on vitamin E has used alpha-tocopherol. The results have shown that alpha-tocopherol is useful as a heart-protective nutrient. Gamma-tocopherol has been shown to have a greater effect than alpha-tocopherol in inhibiting the formation of nitric-oxide-derived free radicals, which appears to be a factor in the origination and development of heart disease.
Researchers at the University of Uppsala, Sweden carried out a study to see whether measurements of blood vitamin E concentrations can contribute to differences between subjects with and without coronary heart disease. Sixty-nine male patients, below 60 years of age, with coronary heart disease were compared with 138 healthy male subjects of similar ages. They found a significantly lower gamma tocopherol concentration and a high ratio between alpha and gamma tocopherol in the coronary heart disease group compared with the healthy subjects thereby indicating a difference in antioxidative status between groups. (Journal of Internal Medicine. 1996 Feb;239(2):111-7).
Alpha tocopherol is not the most potent form of vitamin E. Too much of it can actually hinder the absorption of other types of vitamin E.
Recent studies indicate that gamma-tocopherol may be important to human health and that it possesses unique features that distinguish it from alpha-tocopherol.
While the type of vitamin E usually used in supplements is alpha-tocopherol, research published in the December 2004 issue of the Proceedings of the National Academy of Sciences indicates another form of vitamin E, gamma-tocopherol, but not alpha-tocopherol, inhibits prostate cancer cells from multiplying, without affecting healthy prostate cells.
Rush University's Martha Clare Morris, Sc.D., lead nutrition researcher for CHAP, the Chicago Health and Aging Project, found a 67% lower risk of Alzheimer's in subjects with the highest intakes of vitamin E from food and concluded: "The results suggest that various tocopherol forms rather than alpha-tocopherol alone may be important in the vitamin E protective association with Alzheimer's disease."
Researchers at the University of California conducted a study using rats that concluded there was strong evidence that gamma-tocopherol, but not alpha-tocopherol, showed anti-inflammatory activities that may be important for human disease prevention and therapy. (FASEB J. 2003 May;17(8):816-22).
The importance of this study is that inflammatory diseases such as rheumatoid arthritis, asthma, and hepatitis are among the leading causes of death and disability in the world. Chronic inflammation contributes to the development of degenerative diseases, including cancer, cardiovascular diseases, and neurodegenerative disorders (nervous system degeneration).
Gamma-tocopherol concentrations in the blood have been reported to be significantly lower in coronary heart disease patients compared to healthy subjects, suggesting that the low gamma-tocopherol concentrations increased the risk of coronary heart disease.
Newly recognized properties of gamma-tocopherol provide a basis for its superior cancer preventive activity. A possible reason for the protective effects in the presence of high gamma-tocopherol concentrations is that gamma-tocopherol enhances the cellular uptake of alpha-tocopherol. Our data show that gamma-tocopherol accumulates in colon cancer cells at a twenty fold increase over alpha-tocopherol. Higher concentrations of tocopherols are being tested, but have resulted in cell death in three colon cancer cell lines. (BMC Cancer 2003, 3:25 (1 October 2003) Open access.)
High doses of alpha-tocopherol deplete gamma-tocopherol
These distinguishing features of gamma-tocopherol and its metabolite suggest that gamma-tocopherol may contribute significantly to human health in ways not recognized previously. This possibility should be further evaluated, especially considering that high doses of alpha-tocopherol deplete plasma [blood] and tissue gamma-tocopherol, in contrast with supplementation with gamma-tocopherol, which increases both. (The American Journal of Clinical Nutrition. 2001 Dec;74(6):714-22).
Moreover, we found the presence of gamma-tocopherol dramatically influenced the cellular accumulation of alpha-tocopherol, i.e., gamma-tocopherol promoted the accumulation of alpha-tocopherol. The potential health related significance of gamma-tocopherol is being increasingly recognized. (Nutrition Journal 2002, 1:2).
While alpha-tocopherols are the most widely used, and have enormous health benefits, gamma, beta and delta tocopherols also offer important benefits. Supplementing with mixed tocopherols should derive the benefits of both alpha-tocopherol and gamma-tocopherol, without creating an imbalance in these two forms of vitamin E. Supplements containing this wide variety of vitamin E forms are usually referred to as "mixed tocopherol" or "mixed tocotrienol" supplements.
Remember to take your vitamin E with some sort of fat or oil for better absorption as it is a fat soluble vitamin.
According to [Maret] Traber and [Scott] Leonard, this indicates that people who are taking vitamin E supplements only with liquids on an empty stomach are accomplishing nothing and getting few if any benefits from the supplements. The vitamin clearly is absorbed better if it is part of, or closely associated with the digestion of a food that has some fat in it. (David Stauth, Oregon State University, The Linus Pauling Institute 15/1/2004).
Most vitamin E supplements contain synthetic alpha-tocopherol, but unlike some other vitamins, synthetic vitamin E is not identical to natural. Vitamin E supplements are labelled d-alpha for natural and dl-alpha for synthetic. If the label lists "dl-alpha-tocopherol", it's not the real thing.
This is most clearly shown by comparing natural with synthetic vitamin E. Both have identical antioxidant activities, yet the natural vitamin E has roughly twice the availability of synthetic vitamin E. (The American Journal of Clinical Nutrition. 1998 Apr;67(4):669-84).
Japanese researchers found that natural vitamin E at 100 mg per day was not different from that of 300 mg per day of synthetic vitamin E in seven normal, healthy women aged 21-37 years. (Am J Clin Nutr. 1997 Mar;65(3):785-9).
You can get the best forms of vitamin E through your food. Fruits, green leafy vegetables, whole grains, olive oil, sunflower oil, safflower oil, oily fish (salmon, mackerel and sardines), eggs, natural organ meats and nuts are good sources of vitamin E. Most of these foods give you the entire vitamin E family..
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References
Jiang Q, Wong J, Fyrst H, Saba JD, Ames BN. gamma-Tocopherol or combinations of vitamin E forms induce cell death in human prostate cancer cells by interrupting sphingolipid synthesis. Proc Natl Acad Sci U S A. 2004 Dec 21;101(51):17825-30.
Helzlsouer KJ, Huang HY, Alberg AJ, et al. Association between alpha-tocopherol, gamma-tocopherol, selenium, and subsequent prostate cancer. J Natl Cancer Inst. 2000;92(24):2018-2023.
MC, Evans DA, Tangney CC, Bienias JL, Wilson RS, Aggarwal NT, Scherr PA. Relation of the tocopherol forms to incident Alzheimer disease and to cognitive change. Am J Clin Nutr. 2005 Feb;81(2):508-14.
Jiang Q, Christen S, Shigenaga MK, Ames BN. gamma-tocopherol, the major form of vitamin E in the US diet, deserves more attention. Am J Clin Nutr. 2001 Dec;74(6):714-22. Review.
Gao R, Stone WL, Huang T, Papas AM, Qui M. The uptake of tocopherols by RAW 264.7 macrophages. Nutrition Journal 2002, 1:2 (15 October 2002).
Jiang Q, Ames BN. Gamma-tocopherol, but not alpha-tocopherol, decreases proinflammatory eicosanoids and inflammation damage in rats. FASEB J. 2003 May;17(8):816-22.
Campbell SE, Stone WL, Whaley SG, Qui M, Krishnan K. Gamma (?) tocopherol upregulates peroxisome proliferator activated receptor (PPAR) gamma (?) expression in SW 480 human colon cancer cell lines. BMC Cancer 2003, 3:25 (1 October 2003). This is an Open Access article.
Ohrvall M, Sundlof G, Vessby B. Gamma, but not alpha, tocopherol levels in serum are reduced in coronary heart disease patients. J Intern Med. 1996 Feb;239(2):111-7.
David Stauth, Oregon State University, The Linus Pauling Institute, Study finds huge variability in vitamin E absorption, 15-Jan-2004.
Burton GW, Traber MG, Acuff RV, Walters DN, Kayden H, Hughes L, Ingold KU. Human plasma and tissue alpha-tocopherol concentrations in response to supplementation with deuterated natural and synthetic vitamin E. Am J Clin Nutr. 1998 Apr;67(4):669-84.
Kiyose C, Muramatsu R, Kameyama Y, Ueda T, Igarashi O. Biodiscrimination of alpha-tocopherol stereoisomers in humans after oral administration. Am J Clin Nutr. 1997 Mar;65(3):785-9.
PMID: 9062530.
Kevin Flatt specialisies in Alternative Medicine. He is the publisher of Natural Health Articles And News at and Health Articles by Various Authors.
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