AJCN Aug, 2007 – MULTIVITAMIN LETTER TO EDITOR

This letter to the editor is so powerful and important that I am sending it separately. Written by Bruce Ames at UC-Berkeley and Walter Willett at Harvard, these are probably the two greatest nutritionists alive in the world today. It has been my honor to listen to and argue with both of them about this and other nutritional issues. This is a substantial portion of the letter, and I recommend you go to the link and read it all. In essence, it says, if you do not eat a really good diet, they think you should take a multivitamin. Based on interviews with them this summer, both take a multivitamin without iron. A careful reading of this letter highlights that if you do not eat a really good diet with plenty of fruits and vegetables, it is worthwhile to take a daily vitamin. But other articles in this same issue of AJCN (and many other issues) point out that too much of many nutrients like iron, folate, selenium, vitamin A, etc. can increase your risk of many chronic diseases. It is your personal circumstance and awareness of what you put in your body that is the key to a wise decision. Should you take a multivitamin every day, every other day, never? It is a question worth careful observation of your diet for a while.

[POWERFUL ENDORSEMENT OF MULTIVITAMINS BY BRUCE AMES AND WALTER WILLETT] Evidence-based decision making on micronutrients and chronic disease: long-term randomized controlled trials are not enough ” The State-of-the-Science Conference on Multivitamin/Mineral (MVM) Supplements and Chronic Disease of the National Institutes of Health was held in May 2006…However, the planning committee limited the scope of evidence to long-term randomized controlled trials (RCTs)…we strongly criticize the panel’s decision to base policy recommendations only on evidence from RCTs. This does not make good scientific sense. Policy recommendations should be based on the full range of relevant scientific evidence. ..such RCTs are extremely difficult. They must be conducted for decades to detect effects on long-latency disease incidence, and compliance is difficult to maintain,…The experience of the Women’s Health Initiative trial of vitamin D and calcium (5) exemplifies many of these difficulties—choosing an adequate dose for testing, maintaining a sufficient level of adherence, and conducting the trial for a long enough period to provide an adequate test of hypotheses. Indeed, sensible public policy recommendations for not smoking, physical activity, and weight control provide examples of policy decisions that did not require RCTs. Moreover, RCTs were misleading with respect to smoking (6, 7). Yet, there is a great deal of epidemiologic and mechanistic evidence concerning the effects of micronutrient deficiencies on cancer and other chronic disease endpoints and on biochemical endpoints relevant to chronic disease mechanisms… The panel excluded this highly relevant body of evidence from consideration, and it came to the conclusion, “[T]he present evidence is insufficient to recommend either for or against the use of MVMs by the American public to prevent chronic disease” (2). We contend that, by conveying the impression that long-term RCTs, which are inherently limited, represent the only scientific evidence relevant to “evidence-based decision making,” the panel presents a highly biased and misleading picture.

One of us (BNA), in a report originally prepared for this conference but published elsewhere (3), recently discussed the large body of evidence indicating that deficiencies in many micronutrients cause DNA damage, such as chromosome breaks. Some of these micronutrient deficiencies also cause mitochondrial decay with oxidant leakage and cellular aging and are associated with late-onset diseases such as cancer. Ames also introduced a theory that provides a rationale for why micronutrient deficiencies may lead to greater risk of chronic diseases such as cancer. He proposed that DNA damage and late-onset diseases are consequences of a “triage allocation response” to micronutrient scarcity. Episodic shortages of micronutrients were common during evolution. Because natural selection favors short-term survival at the expense of long-term health, Ames hypothesized that short-term survival was achieved by allocating scarce micronutrients by triage, in part through an adjustment of the binding affinity of proteins for required micronutrients. The hypothesis is testable, and, if correct, it predicts that micronutrient deficiencies triggering the triage allocation response would accelerate cancer, aging, and neural decay but would leave critical short-term metabolic functions, such as ATP production, intact…

Of course, everyone would agree that all persons should be encouraged to eat a good diet, but we are far from achieving this goal, especially among the poor. In most cases, a simple way to improve micronutrient status is to take an MVM. However, even if one eats an ideal diet and takes an MVM, some vitamins can remain below recommended concentrations in some subgroups.

Because MVMs are cheap, readily available, and nontoxic (3), why not recommend that people take an MVM, particularly because much epidemiologic, biochemical, and other evidence points to the need for an adequate supply of vitamins and minerals for optimum function on many levels? At a minimum, taking an MVM is good insurance.

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