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The Boston Globe

Business

Product review

Herbs, vitamins may come with hidden hazards

consumer reports

Consumer Reports recently identified hazards that might surprise the large swath of American adults — more than 50 percent — who take vitamins, herbs, or other nutritional supplements.

The list of hazards was distilled from interviews with specialists, published research, and an analysis of reports of serious, adverse events submitted to the Food and Drug Administration and obtained through a Freedom of Information Act request.

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The hazards include:

Supplements are not risk-free. More than 6,300 reports to the FDA from supplement companies, consumers, health care providers, and others described an excess of 10,300 serious outcomes. Those outcomes included 115 deaths, 2,100 hospitalizations, 1,000 serious injuries or illnesses, 900 emergency room visits, and 4,000 other medical events between 2007 and 2012. The reports by themselves don’t prove that supplements caused the problems, but the raw numbers are cause for concern. Current laws make it difficult for the FDA to order a problem product off the market.

To protect yourself, search the FDA’s website at www.fda.gov for warnings, alerts, or voluntary recalls involving a supplement you are thinking of taking. If you suspect you are having a bad reaction to a supplement, tell your doctor.

Some supplements are really prescription drugs. According to Daniel Fabricant, director of the FDA’s Division of Dietary Supplement Programs, dietary supplements spiked with prescription drugs are the “largest threat” to consumer safety. Many recalled products have the same or similar active ingredients as prescription drugs such as sildenafil (Viagra), tadalafil (Cialis), and sibutramine (Meridia, a weight-loss drug removed from the market in 2010 because of evidence that it increased the risk of heart attacks and strokes). Others contained synthetic steroids. To protect yourself, consult your doctor if you are having trouble in the bedroom.

You can overdose on vitamins and minerals. Unless your health care provider says you need more than 100 percent of the recommended daily intake of a particular nutrient, you probably don’t. Megadoses of the fat-soluble vitamins A, D, E, and K can cause problems, and even some standard doses may interfere with certain prescription medicines.

You can’t depend on warning labels. For one thing, the FDA doesn’t require them on supplements, except for iron. In a market basket study of 233 products purchased online and in the New York metropolitan area, Consumer Reports found wide variations and inconsistencies in labeling. To protect yourself, make sure your doctor or pharmacist knows what supplements and prescription drugs you are taking or thinking of taking.

Heart and cancer protection: not proven. Omega-3 pills and antioxidants are widely thought to reduce the risk of heart disease and cancer, respectively, and millions of women take calcium to protect bones. But recent evidence casts doubt on whether those supplements are as safe or effective as assumed. The widely held view that fish oil pills help prevent cardiovascular disease hit a snag when a study of 12,500 diabetic or prediabetic people with a high risk of heart attack or stroke found no difference in the death rate from cardiovascular disease between those given a 1-gram fish oil pill every day and those given a placebo. These findings were published by the New England Journal of Medicine.

Consumer Reports also notes a recent blow against calcium supplements by German and Swiss researchers who followed almost 24,000 adults for an average of 11 years. They found that regular users of calcium supplements had an 86 percent increased risk of heart attack compared with those who didn’t use supplements, as reported in the June issue of the journal Heart. To protect yourself, lay off the antioxidant supplements and reduce your cancer risk by quitting smoking, avoiding excessive alcohol, and eating a healthy diet.

Consumer Reports writes columns, reviews, and ratings on cars, appliances, electronics, and other consumer goods. Previous stories can be found at consumerreports.org.

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