Experts: Don't Waste Your Money on Multivitamins
Three studies find the supplements don't help extend life or ward off heart disease and memory loss
"No matter which way we broke it down, there was a null effect," said study author Jacqueline O'Brien, a research associate at Brigham and Women's Hospital in Boston. "Supplements are often marketed to have benefits for brain health and things like that, and this is a pretty clear takeaway message."
The same study, however, had previously found that multivitamins might modestly reduce the risk of cancer and cataracts. Cancer risk was reduced by 8 percent, while the risk of cataracts dropped by 9 percent, compared to a placebo.
In the second study, researchers randomly assigned 1,700 heart attack survivors enrolled in a trial of therapy known as intravenous chelation to a daily regimen of high doses of vitamins and minerals or placebo pills.
Participants were asked to take six large pills a day, and researchers think many developed pill fatigue. Nearly half the participants in each part of the study stopped taking their medication before the end of the study. The average time people stuck with it was about two and a half years.
After an average of 55 months, there was no significant difference between the two groups in a composite measure that counted the number of deaths, second heart attacks, strokes, episodes of serious chest pain and procedures to open blocked arteries.
The third study, a research review, assessed the evidence from 27 studies on vitamin and mineral supplements that included more than 450,000 people. That study, conducted for the U.S. Preventive Services Task Force, found no evidence that supplements offer a benefit for heart disease or that they delay death from any cause. They found only a minimal benefit for cancer risk.
The results of the studies are so clear and consistent, the editorial writers said, that it's time to stop wasting research money looking for evidence of a benefit.
"The probability of a meaningful effect is so small that it's not worth doing study after study and spending research dollars on these questions," Guallar said.