Tocotrienols: part of a `vitamin E complex'?

An antioxidant cocktail including vitamin E and its `relatives.'

While everyone has heard of B-complex vitamins, and some have heard of "C complex" (with bioflavonoids), could there be a "vitamin E complex"? Though only one form of vitamin E has, historically, been considered essential, a growing body of research suggests that other members of the vitamin E team play important roles in the body as well.

Most vitamins have a singular natural form, but nature has given us eight vitamin E compounds, each with slight variations in chemical structure. Four of these are called tocopherols and four are tocotrienols. One of these eight, alpha-tocopherol is the form found in most vitamin formulas. This compound is well absorbed in the body and most human cells contain higher levels of it than other members of the vitamin E team. Hence, this form has become the gold standard for dietary supplements and food fortification.

Alpha-tocopherol is a very valuable player. As an antioxidant, it stops free radicals in their tracks before they can wreak havoc on our cells, membranes, and DNA. Free-radical damage can lead to cancer, heart disease, and other diseases associated with aging. Alpha-tocopherol can also decrease LDL and total cholesterol levels, thereby helping to stave off heart disease, the #1 killer of men and women in the US.

Despite these benefits, several researchers are turning their attention to tocotrienols and the other tocopherols and finding that these forms, too, may be part of this E complex. Because all forms of vitamin E exist together in nature, the theory goes, it's likely that all of them are important to health. Vitamin E expert Andreas Papas, Ph.D., author of The Vitamin E Factor (HarperCollins) agrees. "Having the team together means you get a wider spectrum of protection," he explains. Recent tocotrienol research certainly supports that view, especially in the areas of heart disease and cancer.

Here's a brief look at a few studies:

1. Subjects taking mixed tocotrienols in an ongoing, five-year study had improved blood flow in their carotid arteries after 18 months of supplementation, signifying a decreased risk of heart attack. (Tomeo, A.C., et al., Lipids, 1995.)

2. Subjects taking tocotrienols daily for one year experienced significant decreases in triglycerides, total blood cholesterol, and LDL, or "bad" cholesterol levels, in another study. They also had an increase in HDL, or "good" cholesterol, levels. Tocotrienols may decrease the risk of heart disease and slow or even reverse its progression by affecting these levels. (1999 World Congress.)

3. Tocotrienols significantly inhibited the growth and reproduction of human breast cancer cells in vitro, while alpha-tocopherol demonstrated no such effect. (Nesaretnam, Kalanithi, et al., Lipids, 1995.) A later study also found that tocotrienols were effective inhibitors of various breast cancer cells in combination with the common breast cancer drug Tamoxifen. (Guthrie, Najla, et al., Journal of Nutrition, 1997.)

4. Alpha-tocopherol and tocotrienols applied to the skin of mice helped to preserve vitamin E in the skin. Ultraviolet (UV) radiation from the sun and environmental pollutants put oxidative stress on our skin. Applying mixed vitamin E compounds to the skin may offer protection from free-radical damage. (Traber, Maret G., et al., Lipids.)

Optimal levels of vitamin E are difficult to obtain from diet alone, so Papas recommends taking a combination of 100 mg of mixed tocotrienols and tocopherols, as well as 100 IU of d-alphatocopherol daily (the "d" represents the superior, natural form, whereas "dl" refers to the synthetic form). He suggests 400 mg and 400 IU, respectively, for older people or those with a family history of chronic disease. (Caution: anyone taking blood thinners should not take vitamin E except under a doctor's supervision.)

Papas also stresses that antioxidants work best as a complex, so swallowing an antioxidant "cocktail" containing mixed vitamin E forms, vitamin C, selenium, mixed carotenoids, and coenzyme Q10 is ideal.

REFERENCES

Guthrie, Najla, Gapor, Abdul, Chambers Ann F., and Carroll, Kenneth K. "Inhibition of Proliferation of Estrogen Receptor-Negative MDA-MB-435 and - Positive MCF-7 Human Breast Cancer Cells by Palm Oil Tocotrienols and Tamoxifen, Alone and in Combination," Journal of Nutrition 127(3):544S-548S, 1997.

Nesaretnam, Kalanithi, Guthrie, Najla, Chambers, Ann F. Carroll, Kenneth K. "Effect of Tocotrienols on the Growth of a Human Breast Cancer Cell Line in Culture," Lipids 30(12): 11391143, 1995.

Tomeo, A.C., Geller, M., Watkins, T.R., Gapro, A., and M.L. Bierenbaum. "Antioxidant Effects of Tocotrienols in Patients with Hyperlipidemia and Carotid Stenosis," Lipids 30(12): 1179-1183, 1995.

Traber, Maret G., Rallis, Michalis, Podda, Maurizio, Weber, Christine, Maibach, Howard I., Packer, Lester. "Penetration and Distribution of a-tocopherol, a- or y-Tocotrienols Applied Individually onto Murine Skin," Lipids 33(1):8791.

Watkins, T.R., Kooyenga, D.K., and M.L. Bierenbaum. "Hypocholesterolemic and antioxidant effect of rice bran oil nonsaponifiables in hypercholesterolemic subjects," Oxidants and Antioxidants in Biology, Oxygen Club of California, 1999 World Congress.

Liz Brown is a freelance health and nutrition writer based in Portland, Oregon. Since earning a B.S. in Nutrition at the University of Minnesota, she has contributed regularly to several newspapers and magazines.

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