When it comes to nutritional advice, don’t believe everything you read in the mainstream news. News reporters are seldom knowledgeable enough about nutrition to report results accurately (and have been known to jump to conclusions not intended by the studies’ authors) and reporters are certainly not competent enough to spot and question flaws in the studies. Also while medical experts are often interviewed to add caution to studies which show nutrient supplementation in a positive light, rarely are nutritional experts interviewed in a negative story. Here are two recent news stories that demonstrate these biases.
In December 2011 a study was published in JAMA that showed that vitamin E increases the risk of prostate cancer. A CBC report on the study quoted the chief medical officer for the American Cancer Society (who was not involved in the study) advising men to avoid high doses of vitamin E, but then extended his warning to all vitamins: “…excessive use of vitamins has not been proven to be beneficial and may be the opposite”. A representative of the Council for Responsible Nutrition (a supplement manufacturers’ association) was generously given the last word, reassuring the readers of the benefits of vitamin E as an essential nutrient and suggested that many Americans don’t get enough. But even he missed the biggest flaw in the study, pointed out in a critique by Health Sciences Institute, that the vitamin E used in the study was the poorly utilized synthetic dl-alpha tocopherol acetate form instead of the natural d-alpha tocopherol form. Had they used natural vitamin E, I believe the results would have been much different. The only conclusion that can be made from this study is that synthetic vitamin E should be avoided.
Then in June 2012 the United States Preventive Services Task Force published a statement that low doses of calcium (1000mg) and vitamin D (400iu) do not prevent fractures in healthy postmenopausal women and are better avoided. The result is, I’m sure, quite accurate but the recommendation to avoid them is misguided at best. I’ll explain more about the flaws in this study in next week’s column.
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.
The fact that synthetic vitamin E increased prostate cancer rate should be a caution to taking large doses of any kind of vitamin E including natural forms, at least until further research is done. But who knows when that will be, if ever. I'd like to point out that when a pharmaceutical drug is found to have a serious side effect, other members of that drug family are taken a closer look at but not immediately banned.
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