Vitamins, minerals: Too much can be harmful
KEY POINT
New studies show that use of vitamin and mineral supplements may be associated with an increased risk of death in older women and that commonly used doses of vitamin E raised the risk of prostate cancer in healthy men. The studies support a U-shaped risk curve, indicating that too little and too much can both be detrimental.
SOURCES
Mursu J et al. Dietary supplements and mortality rate in older women: The Iowa Women's Health Study. Arch Intern Med. 2011;171:1625–33.
Bjelakovic G et al. Vitamin and mineral supplement use in relation to all-cause mortality in the Iowa Women's Health Study. Comment on “dietary supplements and mortality rate in older women.” Arch Intern Med. 2011;171:1633–4.
Klein EA et al. Vitamin E and the risk of prostate cancer: results of the Selenium and Vitamin E Cancer Prevention Trial (SELECT). JAMA. 2011; 306:1549–56.
