Study: Calcium Supplements May Increase Heart Attack Risk
Calcium supplements may double the risk of heart attacks, a new study suggests. Swiss and German researchers tracked nearly 24,000 people for 11 years, and found that while dietary calcium seems to protect against heart attacks and strokes, supplements may boost that risk. "Instead of taking calcium supplements, men and women who want to increase their calcium intake should rely on foods, such as low-fat dairy products or mineral water, [that are] rich in calcium," study author Sabine Rohrmann, an assistant professor of chronic disease epidemiology at the University of Zurich in Switzerland, told HealthDay. Though the researchers found a link between calcium and heart attacks, they cannot explain why, and the study does not show cause and effect. "I am doubtful of these findings," Robert Recker, director of the Osteoporosis Research Center at Creighton University, told HealthDay. "It's hard to understand why calcium in the diet can reduce the risk of heart attack, but supplements increase the risk."
Vitamins and Supplements: Do They Work?
Vitamins and dietary supplements are big—more than 110 million Americans forked over a collective $28 billion in 2010 on little bottles of would-be health magic. Research is unclear, however, on whether shoring up your diet with extra vitamins, minerals, and other supplements helps or hurts—in the short run or in reaching for the century mark.
For more than a decade, for example, researchers followed more than 35,000 men enrolled in SELECT, a clinical trial designed to see whether taking selenium and vitamin E might help prevent prostate cancer. In 2008, study participants received phone calls and letters: Stop the pills. Not only was the answer "no," but vitamin E apparently increased the chance of prostate cancer, if very slightly, and selenium seemed to do the same to diabetes risk. Later the same year, researchers from the Physicians' Health Study-II reported that neither vitamin E nor vitamin C reduced the chances of major cardiovascular problems or cancer as hoped.
That so many people seem to believe they need to boost their intake of vitamins and supplements is a triumph of marketing. Most Americans are well-nourished (besides being amply fed). Because much of our food is fortified with nutrients, once-common deficiency diseases such as scurvy and rickets, caused by inadequate vitamin C and D, respectively, have nearly disappeared in this and other developed countries. Researchers generally believe that with a few exceptions, like pregnant women or the elderly, most people don't need supplements. Over the 22-year course of the Iowa Women's Health Study, supplemental vitamin B6, folic acid, iron, magnesium, and zinc were associated with a slightly higher risk of premature death, copper to an 18 percent increased risk. Findings were published last year in the Archives of Internal Medicine. The study authors highlighted concerns about the long-term use of supplements and vitamins among those who do not have severe nutritional deficiencies. The pills, they concluded, are best used when recommended by doctors—not for general prevention. [Read more: Vitamins and Supplements: Do They Work?]
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4 Herbal Supplements Your Doctor Hates
More than half of Americans have taken a dietary supplement, and it's easy to see why. Popping a pill is painless. Supplements don't require a prescription from a doctor. And there's always some hale bloke out there who will vouch for the miraculous health improvements he experienced while taking this or that herbal remedy.
Plus, herbals often seem safer than drugs and other treatments. If a supplement can be found on stores' shelves alongside healthy foods, it must be wholesome, right?
Wrong. Of the 30,000 products rated by the Natural Medicines Comprehensive Database, an independent research and publishing organization, less than one percent earned a top score for safety, effectiveness, and quality.
Unlike prescription medications, dietary supplements aren't reviewed or approved by the FDA before they go on sale. And, although manufacturers have been required to prove that new supplements are "reasonably expected to be safe" since 1994, a recent report in the New England Journal of Medicine found that this law is largely unenforced.
"Consumers have the idea that the people who are selling herbal remedies are doing it out the goodness of their hearts," says Lauren Streicher, assistant professor of obstetrics and gynecology at Northwestern University's Feinberg School of Medicine. But supplement makers are even more profit-driven than pharmaceutical companies, which are subject to FDA review, she says. "Does the FDA make mistakes? Yes. But they're the only protection we've got to make sure greed doesn't get in the way of science." [Read more: 4 Herbal Supplements Your Doctor Hates]
Angela Haupt is a health reporter for U.S. News & World Report. You can follow her on Twitter or reach her at firstname.lastname@example.org.