A multivitamin-multimineral supplement can fill in micronutrient gaps in your diet.
The precise requirements for various vitamins have
been controversial since their discovery in the late 1800s and early 1900s. The
early recommendations were based on the amounts needed to avoid so-called
diseases of deficiency such as scurvy (too little vitamin C), beri-beri (too
little vitamin B1), pellagra (too little vitamin B3), and rickets (too little
vitamin D). Ongoing research suggests a broader role for vitamins. Work by Dr.
Bruce N. Ames of the University of California, Berkeley,
and others shows that deficiencies in many micronutrients can lead to damage to
DNA, the essential "blueprint" of each cell. (1) Such damage can
cause or accelerate aging-related conditions. (2) This would make chronic
conditions such as cancer, heart disease, vision loss, and a host of others a
new type of deficiency disease.
5 Quick Tips for Getting the Right Vitamins: Read more about vitamins with newly recognized or suspected roles in health and disease.
A diet chock full of fruits, vegetables, whole grains, good protein packages, and healthy fats should provide all the nutrients needed for good health. But not everyone manages to eat a healthful diet, or get enough vitamin D from the sun, and some older people have trouble absorbing vitamin B12 from food. When it comes to micronutrients, a significant fraction of people get less than the Estimated Average Requirement set by the Institute of Medicine.
That's why we believe a daily multivitamin-multimineral pill offers safe, simple micronutrient insurance. You don't need an expensive "designer" supplement or a name-brand kind. A standard store-brand multivitamin-multimineral supplement is fine. Look for one that contains the Recommended Dietary Allowance (RDA) and that also has the United States Pharmacopeia (USP) seal of approval on the label. The amount of vitamin D in most such supplements is usually 400 IU, so you might want to look for one that contains 1,000 IU of vitamin D or get additional amounts from a separate vitamin D supplement as well. In fact, the desirable intake of vitamin D is shifting swiftly; we are finding that many people need 3,000 to 4,000 IU to get their blood levels of vitamin D into an adequate range.
Some scientists believe there is not enough evidence to recommend for or against taking a daily multivitamin, because there isn't yet enough data from randomized controlled trials. (3) That's a short-sighted point of view since it may never be possible to conduct randomized trials that are long enough to test the effects of multiple vitamins on risks of cancers, Alzheimer's disease, and other degenerative conditions. Looking at all the evidence—from epidemiological studies on diet and health, to biochemical studies on the minute mechanisms of disease—the potential health benefits of taking a standard daily multivitamin far outweigh the potential risks. (4)
References
1. Ames BN, Wakimoto P. Are vitamin and mineral deficiencies a major cancer risk? Nat Rev Cancer. 2002; 2:694-704.
2. Ames BN. Low micronutrient intake may accelerate the degenerative diseases of aging through allocation of scarce micronutrients by triage. Proc Natl Acad Sci USA. 2006; 103:17589-94.
3. National Institutes of Health State-of-the-Science Conference Statement: multivitamin/mineral supplements and chronic disease prevention. Am J Clin Nutr. 2007; 85:257S-264S.
4. Ames BN, McCann JC, Stampfer MJ, Willett WC. Evidence-based decision making on micronutrients and chronic disease: long-term randomized controlled trials are not enough. Am J Clin Nutr. 2007; 86:522-3; author reply 523-4.