WASHINGTON - There's more disappointing news about multivitamins: Two major studies found popping the pills didn't protect aging men's brains or help heart attack survivors.
Millions of Americans spend billions of dollars on vitamin combinations, presumably to boost their health and fill gaps in their diets. But while people who don't eat enough of certain nutrients may be urged to get them in pill form, the government doesn't recommend routine vitamin supplementation as a way to prevent chronic diseases.
The studies released Monday are the latest to test if multivitamins might go that extra step and concluded they don't.
"Evidence is sufficient to advise against routine supplementation," said a sharply worded editorial that accompanied Monday's findings in the journal Annals of Internal Medicine.
After all, most people who buy multivitamins and other supplements are generally healthy, said Cynthia Mulrow, a doctor who is the journal's deputy editor. Even junk foods often are fortified with vitamins, while the main nutrition problem in the United States is too much fat and calories, she added.
But other researchers say the jury's still out, especially for the country's most commonly used dietary supplement - multivitamins that are taken by about a third of U.S. adults, and even more by people over the age of 50.
Indeed, the U.S. Preventive Services Task Force is deliberating whether vitamin supplements make any difference in the average person's risk of heart disease or cancer. In a draft proposal last month, the government advisory group said for standard multivitamins and certain other nutrients, there's not enough evidence to tell. (It did caution that two single supplements, beta-carotene and vitamin E, didn't work). A final decision is expected next year.
"For better or for worse, supplementation's not going to go away," said Howard Sesso of Brigham and Women's Hospital in Boston. He helps lead a large multivitamin study that has had mixed results - suggesting small benefits for some health conditions but not others - and says more research is needed, especially among the less healthy.
Still, "there's no substitute for preaching a healthy diet and good behaviors" such as exercise, he said.
Multivitamins have grown more popular in recent years as research showed that taking high doses of single supplements could be risky, such as beta-carotene.
Multivitamins typically contain no more than 100 percent of the daily recommended amount of nutrients. They're marketed as a safety net for nutrition gaps; the industry's Council for Responsible Nutrition says they're taken largely for general wellness.
With Alzheimer's on the rise as the population ages, Harvard researchers wondered if long-term multivitamin use might help keep older brains agile. They examined a subset of nearly 6,000 male doctors, 65 or older, who were part of a larger study. The men were given either multivitamins or dummy pills, without knowing which they were taking.
After a decade of pill use, the vitamin-takers fared no better on memory or other cognitive tests.