Should We Take Multivitamins?

Traditionally, any medical debate over the health benefits of taking multivitamins has been between those who think they help and those who think they neither help nor hurt. Now, the popular health newsletter Harvard Men's Health Watch has challenged the conventional wisdom, questioning whether these popular supplements might be bad for some of us.

Other studies have linked high dietary intake of folic acid to polyps in the large intestine, a known cancer precursor. Harvard Men's Health Watch has challenged the conventional wisdom, questioning whether these popular supplements might be bad for some of us.

The March 2008 issue cites recent studies that link multivitamin use to prostate cancer. Other studies have linked high dietary intake of folic acid to polyps in the large intestine, a known cancer precursor. Experts speculate that folic acid, which was added to grain products by food manufacturers beginning in the 1990s, may be behind the mysterious increase in colorectal cancers that occurred in the mid−1990s.

With folic acid being added to grain products, the argument goes, a person taking daily multivitamins, along with eating what they think is a healthy diet, could be taking in 1,000 mcg (micrograms) of folic acid or more. Amounts this high are thought to raise the risk of colorectal, prostate and breast cancers.

Harvard Men's Health Watch advises its readers to stop taking multivitamins until further research on the connection between folic acid and cancer. They add, however, that if you follow this advice, you should consider replacing your multivitamin with a vitamin D supplement, as the average American diet does not contain enough of this crucial vitamin.