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Medicine for People! Mid-November 2004 Contents
Are Vitamin E Supplements Harmful? The Annals of Internal Medicine published a study recently titled"Meta-Analysis: High-Dosage Vitamin E Supplementation May IncreaseAll-Cause Mortality." The newspapers headline writers couldn't resistmaking a good story better, so we've had a number of patients call,concerned that use of vitamin E might be harming them. The short answer is that I don't think so. Here are the details. First, point your browser at to see thepaper itself. What these authors did was to locate 36 studies which, amongother study observations, recorded death rates and doses of vitamin E. Ofthese, they selected 19 to include in their summary analysis. In all these studies, overall death rate of study participants wasrecorded, as well as their approximate dose of vitamin E. Look at figure 3 at to seea graph of death rates versus dose of vitamin E. There are 19 circles onthe graph, the larger circles associated with larger studies. The higherthe circle is above the baseline, the higher the death rate in the study.The further the circle is to the right, the higher the dose of vitamin E.If increasing doses of vitamin E clearly increased death rates, you'd see aseries of cicles extending from the lower left corner of the graph to theupper right corner. Nature isn't always that simple, so mathematicianswill often impose a curve on the data points to get an idea of the generalrelation. As you can see from figure 3 above, the data points are prettymuch scattered over the entire graph. In nine studies, vitamin Esupplements appeared to be harmful; in eight studies vitamin E appeared tobe beneficial, and in one study it appeared to make no difference. Theauthors have superimposed their mathematical curve on the figure toindicate that according to the statistical method they chose, that the riskseems to very slightly rise with increasing dose of vitamin E. The reasons I find this study underwhelming are: 1. The study participants all had serious chronic illnesses. As the study authors note "High-dosage (400 IU/d) trials were often small and wereperformed in patients with chronic diseases. The generalizability of theindings to healthy adults is uncertain." 2. Remember that many of the studies represented in figure 3 were small studies looking at the effect of vitamin E and other nutrients on heart disease, colonic polyps, osteoarthritis, eye disease, muscular diseases, and so forth, and were not designed to look at the safety of vitamin E.Then look at figure 3. Take away the curve that the study authorssuperimpose. Look at the circles spread almost at random over the graph and ask why they do not demonstrate a convincing relationship between doseand death rates for vitamin E. If higher doses are truly harmful, why dothe studies abbreviated PPS, GISSI, and ADCS have circles below the line ofneutral effect and show that in those studies higher doses appeared to be beneficial? HOPE and GISSI are two large studies that showed either noharm, or showed a positive benefit. This is why the authors titled theirstudy "may increase." I don't think it looked too convincing to them either. 3. Again looking at figure 3, note the circle labeled CHAOS (which stands for Cambridge Heart Antioxidant Study), which, on figure 3, makes the statistical curve rise and indicate a risk from vitamin E. Then read the abstract by the authors of that study, who state "the ... excess of cardiovascular deaths in the alpha-tocopherol group ... wasnon-significant... We conclude that in patients with angiographically proven symptomatic coronary atherosclerosis, alpha-tocopherol treatmentsubstantially reduces the rate of non-fatal MI, with beneficial effects apparent after 1 year of treatment." Translation: In people with blocked arteries vitamin E reduced heart attacks. So, the Cambridge University folks thought vitamin E was helpful, but this new study takes a little piece of their work and puts a different slant on it. Which leads us to the primary reason people take vitamin E. Certainly
onecan hope that one will live longer, but the more compelling
reason is thatone will maintain good health throughout more of
the life span.
Mixed Tocopherols
Finally, there are several forms of vitamin E, and I doubt if any of thesestudies used the most physiologic form of supplemental vitamin E, which ismixed tocopherols. Most vitamin E supplements are alpha-tocopherol, butevidence is mounting that the beta, delta, and gamma tocopherols areimportant as well. Higher doses of alpha-tocopherol could interfere withthe absorption of the other forms of vitamin E. This could, in someone whois ill, lead to harm from deficiency of the beta, delta, and gamma forms.The interaction of different tocopherols is still unclear. To be on thesafe side, we currently recommend mixed tocopherols to our patients. Youcan see our patient handout on vitamin E at for more information. Based upon my reading of the research, and my understanding of humanmetabolism, my bet is that time and further research will demonstrate thatdoses of mixed tocopherols in the range of 1000 I.U. per day will, for most adults, increase well-being and slow the deterioration of aging.
Mail Order Drugs - Proceed with Caution Because the price of prescriptions has skyrocketed, many people areordering mail order drugs through the Internet from Canada. If your drugis a generic, ordering from Canada will not be cheaper, but for brand-namepharmaceuticals Canadian prices are lower. There are, however, hazards inpurchasing medicine over the Internet. People have ordered drugs on the Internet from what looked like a Canadianpharmacy and received a package with a Thai stamp. Surveys of drugs comingfrom that part of the world indicate that 30 percent of the packagescontain no active drug. What you're buying is just very professionallooking packaging. In Nigeria it is worse; counterfeiters have replaced 60percent of the pharmaceuticals in that country with inactive substances.Wags may argue that is a good thing, but if you want the activepharmaceutical, you need to be careful. If you have any doubts about ordering drugs online, you can go tothe Washington State Consumer Resources Website for help in finding a reliableCanadian drug connection.
Medicine for People! is published by Douwe Rienstra, MD at Port Townsend, Washington. Edited by Carolyn Latteier. Subscribe | Previous issues | Contact Dr. Rienstra | More information |
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