Food for Thought
Have you ever been asked by a client if vitamins work? Two new studies have raised doubts among nutrition experts as to whether vitamins can protect against cardiovascular disease (CVD) or reduce the risk of certain cancers. Both studies involved large demographic groups that were closely monitored during long-term, randomized clinical trials.
The first study, which involved more than 5,400 women enrolled in the Women’s Antioxidant and Folic Acid Cardiovascular Study, examined whether taking a combined supplement of folic acid, vitamin B6 and vitamin B12 had any effect on cancer risk in females who were at high risk of either total invasive cancer or breast cancer. The women, who were 42 or older and had preexisting CVD or three or more coronary risk factors, were randomly assigned to receive the vitamin combination or a placebo. Those who took the combined supplements were given daily doses of 2.5 milligrams (mg) of folic acid, 50 mg of vitamin B6 and 1 mg of vitamin B12.
At the end of the 7-year study period, the results were disappointing in terms of reducing cancer risk. Writing in the November 5, 2008, issue of the The Journal of the American Medical Association (JAMA) (300 , 2012–21), the authors drew the following conclusion: “Combined folic acid, vitamin B6 and vitamin B12 treatment had no significant effect on overall risk of total invasive cancer or breast cancer.”
In the second study, researchers observed 14,641 male health professionals (age 50 and older) who were involved in the Physicians’ Health Study. The goal of the study was to evaluate whether long-term intake of vitamin E and vitamin C supplements would decrease the risk of major CVD events among men. During this randomized, double-blind study, the men were given either a placebo, individual supplements of 400 international units of vitamin E every other day or daily doses of 500 mg of vitamin C.
Once again, the findings were dismal: “In this large, long-term trial of male physicians, neither the vitamin E, nor vitamin C supplementation, reduced the risk of major cardiovascular events,” the authors concluded in the November 12, 2008, issue of JAMA (300 , 2123–33). “These data provide no support for the use of these supplements for the prevention of CVD in middle-aged and older men.”
The bottom line: men and women should focus less on vitamin supplementation and more on eating a balanced diet of whole foods to obtain the nutrients needed to remain healthy.