From the American Society for Nutritional Sciences, in noting an award to Simin Meydani, Ph.D.*, said "She and her colleagues are particularly noted for their discovery in healthy elderly that vitamin E ... enhances T-cell 'immune system] ... function by reducing 'our] immune-suppressing… prostaglandin E2"

Dr. Meydani observed that as we age, our internal production of potentially harmful prostaglandin E2 is increased. But we add that this substance is reduced, not only by vitamin E, but also by aspirin and some foods, notably green tea and fish oils. So, we reduce or prevent a weakening of our immune system, which is our defense against infection, by taking vitamin E. Now the question arises—should we take natural or synthetic E and how much?

Dr. Meydani has also shown that taking 800 i.u. (International Units) had no ill effects on human volunteers. Research by others indicates that, as with other vitamins, like vitamin C, it is better to take smaller doses more frequently rather than large doses at one time.

Here is what scientists have found about the relative merits of natural vs. synthetic E; Ogihara (J. of Nutr Sci Vitaminol) showed that vitamin E levels in red blood cells were much higher after taking natural E orally than with synthetic. Incidentally, natural is designated d-a-tocopherol and synthetic as all-rac-a-tocopherol. Your vitamin purveyor may call natural just that and merely omit any description for the imitation type. If the ad or bottle reads vitamin E only, it probably is synthetic.

Also, Burton & Ingold (Acc Chem Res & Lipids) found that the tissue levels of E were retained much longer with the natural than with the synthetic. Traber etal (J of Lipid Res) discovered that one day after administration, red blood cells in humans were four times richer in E with the natural than after taking the synthetic vitamin.

*Senior Scientist at Tufts University's U.S.D.A. Human Research Center on Aging