“For a lot of people, multivitamins add an extra layer of security to ensure they’re getting at least basic levels of the essential vitamins and minerals,” says Howard Sesso, an epidemiologist at Brigham and Women’s Hospital in Boston and the Harvard Medical School.
But whether multivitamins go beyond that and actually prevent disease remains a very open question, he cautions.
Sesso helped run the largest and longest clinical trial of multivitamins in men.
Men taking Centrum Silver
In the Physicians’ Health Study II, more than 14,000 men took either Centrum Silver, the basic multivitamin-and-mineral for people 50 and older, or a placebo every day for 11 years.
The results? The multi-takers had an eight percent lower risk of being diagnosed with cancer and a nine percent lower risk of developing cataracts.
However, the multi-takers were just as likely to develop cardiovascular disease, suffer cognitive changes, and to die during the study as the placebo-takers.
What about women?
“What we don’t know is how these results apply to other people, especially women,” Sesso cautions.
“While we found a lower cancer risk in men who take a multivitamin, we don’t know whether that’s going to extend to women,” he says. “It might be in women that there’s also a benefit, or maybe there’s an unexpected risk.” Until we conduct more clinical trials, we won’t have definitive answers, says Sesso.
Enter the COSMOS trial
That’s a major reason why the Brigham and Women’s Hospital in Boston, a major teaching affiliate of Harvard Medical School, is recruiting both female and male volunteers for a new clinical trial of multivitamins called the COSMOS trial. The men must be at least 60 years old, the women 65.
Participants will be randomly assigned to take either a Centrum Silver or a placebo every day for four years. They’ll be “blind,” meaning they won’t know which they’re taking until the study is completed. Participants will also be randomly assigned to take two cocoa extract capsules or two placebo capsules every day, as well.
(Centrum, which has a long history of donating its multi for research, will have no role in conducting the study or in interpreting the results.)
Everyone involved must permit the researchers to review their medical records during the trial, but all medical information will be kept strictly confidential. Those who have ever had a heart attack or stroke or who have been diagnosed with cancer within the past two years are not eligible.
For more information, email COSMOStrial@partners.org or call 800-633-6913.
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