|
A few weeks ago the media devoted a lot of attention to some negative studies on nutritional supplements. One of these studies, published in the October 10, 2011 edition of Archives of Internal Medicine, claimed to have found an association between use of multivitamins in elderly women and decreased lifespan. Supplemental vitamin B6, folic acid, magnesium, iron, zinc, and copper were all associated with slightly decreased lifespan. On the surface (and as the media reports it) this does sound alarming. Next month I would like to delve more into legitimate concerns about the safety of supplements in general and some related topics, but for now let's look at this study.
On closer review of the study, there are major shortcomings revealed. Most importantly is the design of this study. It was simply an observational study. A group of women were asked about their vitamin use in 1986, 1997, and in 2004. Of the 38,772 women studied, 15,594 had died by December 31, 2008. The investigators then attempted to tease out how much (if any) blame for these deaths could be placed on vitamin use. Their conclusion was: "In older women, several commonly used dietary vitamin and mineral supplements may be associated with increased total mortality risk; this association is strongest with supplemental iron. In contrast to the findings of many studies, calcium is associated with decreased risk." Take note of the very important word "may". Observational studies are among the weakest type of studies. Nothing of real value is learned from such a study- they don't prove cause and effect.
For example, the study does not tell us if there were some other important differences between the supplement users and nonusers. When people get a diagnosis of a serious health condition such as cancer or heart disease, for example, they often begin taking supplements. People with such diagnoses are more likely to die younger than those without.
This study did not delineate the types of vitamins people took. There is not one single thing described by the word multivitamin. Some are better than others and an occasional one is downright harmful (due to toxicity such as lead contamination). Some forms of supplements are better absorbed than others. Potencies vary tremendously from product to product. Some multivitamins may contain a variety of herbs, the quality of which and appropriateness for each individual can vary. Some supplements contain artificial dyes and other toxic ingredients.
A major problem with many sensational negative studies on supplements is the form of nutrient that is used in the study. This is certainly seen in the case of vitamin E. Vitamin E is actually not one vitamin. There are 8 different vitamin E molecules (alpha, beta, delta, and gamma tocopherol and alpha, beta, delta, and gamma tocotrienols). Our bodies are designed to use all eight forms. If you take a lot of just one of these, you create an imbalance and impair the important health-promoting effects of the others. Many studies on vitamin E, utilize d,l-alpha tocopherol, which is actually worse than using just one vitamin E. It is a synthetic form of one vitamin E. Natural vitamin E only exists in the "d" form. The "d, l" form is 50% natural type and 50% mirror-image vitamin E molecules. The "mirror-image" does not fit into vitamin E receptors in the body as well as the natural molecule does. Natural forms of vitamin E have been found to protect against the development of prostate cancer, heart disease, Alzheimer's disease, frailty in old age, breast cancer mortality, and much more. Synthetic or even incomplete (d-alpha tocopherol only) vitamin E supplementation may be expected to produce harm by interfering with the natural functions of vitamin E. I have known this for many years. Studies utilizing synthetic vitamin E continue to be published. Are the researchers simply ignorant to the facts I just discussed? Or is there a darker, more sinister explanation for the continued investigations into nutritional supplements that can be counted on to show negative results, harm people, and dissuade the public from using nutritional supplements?
When it comes to supplements studies, negative is "hot." Perhaps that is true of news in general. The media is just waiting to advertise a headline like,"Is your multivitamin killing you? Story at eleven." The media doesn't care and is not equipped to examine the validity and true newsworthiness of nutritional studies. They print and air what sells. They could very well be publicizing other stories like the observational study that found use of glucosamine sulfate and use of chondroitin sulfate were both associated with increased life expectancy (Pocobelli, G. Total mortality risk in relation to use of less-common dietary supplements. Am J Clin Nutr. 2010 Jun;91(6):1791-800. Epub 2010 Apr 21.). Likewise, as I mentioned in last month's newsletter on vitamin D, a meta-analysis of 18 studies found that supplementing with vitamin D reduced the risk of dying by 7%. Why hasn't the media reported that a study of multivitamin users found they had longer telomeres? (Xu Q, Parks CG, DeRoo LA, Cawthon RM, Sandler DP, Chen H. Multivitamin use and telomere length in women. Am J Clin Nutr. 2009 Jun;89(6):1857-63. Epub 2009 Mar 11) . Telomeres are the protective caps on the ends of the chromosomes and are a measure of biological age. This study found multivitamin users to be biologically younger. The list of positive, impressive, life-changing results from supplement use is overwhelming. Unfortunately, you can't expect to hear a lot of this from the media.
|
