With osteoarthritis, knees become swollen and stiff, and cartilage can degenerate.
Ted Kinsman/Science Source
October 14, 2013 Glucosamine and chondroitin have been popular supplements for arthritis for years. But clinical trials in humans haven't shown that they're any better than sugar pills at reducing pain. Some doctors say that if placebos or supplements help people exercise and lose weight, then that's OK.
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If only it was as simple as popping a supplement and being set for life. But alas, no.
October 12, 2013 A review of clinical trials using vitamin D to build bone density in middle-aged women finds that it doesn't help. That may be because those women aren't generally low on calcium and that D helps the body absorb calcium in the gut only if it's seriously lacking. It may do more good in the elderly.
Ads often tout dietary supplements and vitamins as "natural" remedies. But studies show megadoses of some vitamins can actually boost the risk of heart disease and cancer, warns Dr. Paul Offit.
July 23, 2013 Physicians are partly to blame for the increasing popularity of untested treatments, says Dr. Paul Offit. Rather than pushing back against misguided patient demand, he says, doctors have "acted like waiters at a restaurant, simply asking, 'What would you like?' "
Raw, green coffee beans. To roast or not?
June 14, 2013 An extract from raw, green coffee beans has been called a "miracle" weight-loss aid. But a study in mice casts doubt on the supplement's fat-burning effects — and even offers preliminary evidence that it could be harmful.
Over the past several years, the FDA has deemed many dietary supplements to be "tainted" by unapproved drugs.
April 23, 2013 More than 200 dietary supplements have been recalled in recent years because they contain drugs that aren't listed on the label, an analysis finds. The ingredients are potentially harmful, researchers say.
April 4, 2013 The Food and Drug Administration says it can't keep up with all the dietary supplements that claim to enhance sexual performance. Many have been found to contain potentially harmful ingredients, so the agency is warning people to beware of the entire bunch.
Forgoing calcium supplements is a fine approach for most people, a preventive services panel says.
February 25, 2013 There's no evidence that calcium supplements help prevent bone fractures in most people, a preventive services task force says. And calcium supplements boost the risk of kidney stones, and perhaps heart disease.
Some sports supplements contain the ingredient DMAA. The FDA has warned that DMAA may not be safe.
February 15, 2013 Exercise buffs who take dietary supplements with the ingredient know as DMAA say the stimulant gives them a boost of energy. But some researchers and the Food and Drug Administration are worried that these products could be dangerous.
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Despite public health campaigns urging women in the U.S. to take folic acid, many are still not taking the supplements when they become pregnant.
February 12, 2013 A study of more than 85,000 women in Norway found that those who started taking a folic acid supplement four weeks before getting pregnant were about 40 percent less likely to have a child who developed the disorder. Mothers had to continue taking the supplement during the first eight weeks of pregnancy to get the full benefit.
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There might be much more caffeine than you think in those supplements you're taking. There also might be much less.
January 9, 2013 A chemical analysis funded by the Defense Department finds that some dietary supplements contain far more caffeine than the amount listed on their labels. Other energy-boosting supplements contain less caffeine than the labels claim.
Federal health officials recommend 1,000 milligrams of calcium per day for people younger than 50, but some are overdoing it.
August 13, 2012 Calcium has been touted to stave off osteoporosis and promote bone health. But new research suggests going overboard on calcium consumption could lead to kidney stones or even a heart attack.
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Can you fight fat with a spoonful of these?
May 12, 2012 Black pepper and other spicy foods are often touted as weight loss aides, thanks to ingredients like capsaicin, but saying no to the freshly-grated Parmesan is more likely to help you lose weight.
Staying fit and eating well can help cancer survivors, too, a review of the latest evidence shows.
April 26, 2012 The American Cancer Society says there's strong evidence that an active lifestyle and a diet rich in fruits and vegetables can help cancer survivors live longer and stay cancer-free. But the latest guidelines take a dim view of nutritional supplements, which experts say can be harmful.
April 19, 2012 The Aztec people believed chia seeds gave them the power to run faster and longer. Today, they're the latest healthy diet trend. But don't eat those old holiday gifts growing out of clay pots, the company recommends.
December 6, 2011 Federal regulators want companies to stop selling homeopathic human chorionic gonadotropin to help people lose weight to stop. The regulators said the marketing of the products makes them "unnapproved new drugs" and that's against the law.
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