Are your supplements safe?

Nutrition Action Healthletter, Nov, 2003 by David Schardt

"We dropped hydroxycitrate when we saw that it seemed to cause testicular atrophy and other toxicities in animals," said a Hoffmann-La Roche spokesperson. "We never got as far as testing it in humans."

When told about the potential problems, a spokesperson for the firm that produces one of the two most popular hydroxycitrate formulations sold in the U.S. said, "I'm really, really surprised."

"There's no incentive for supplement companies to study the safety of their products," says Palmer. "It would be nothing but trouble for them, because they have a good deal right now." If anything's going to hurt their sales, "it's going to be safety issues. So why would they go looking for trouble?"

Take usnic acid. It's produced by lichen plants, so it falls within the loose definition of a dietary supplement. You can buy it on the Internet in the form of Usnea Lichen liquid herbal extracts. (We found one corn party that sells bottles of usnic acid capsules "for experimental research use only and not for human consumption" to anyone who claims to be at legist 18 years old.)

Yet usnic acid may have destroyed the livers of at least half a dozen people in the U.S. over the past few years. Apparently that's not enough to motivate the companies that sell it--or the FDA--to investigate its toxicity.

"I don't know anyone else who's working on the toxicity of usnic acid besides me," says Nell Kaplowitz, director of the University of Southern California Research Center for Liver Diseases in Los Angeles.

* Underreported reactions. "Mild symptoms are definitely underreported to physicians and health agencies, and, as a result, there are probably many problems with supplements that am not being described," says toxicologist Christine Haller. A 2001 report by the U.S. Department of Health and Human Services estimated that only about one out of every 100 adverse reactions is reported to the FDA.

"People are somewhat embarrassed when they have a problem with a supplement that they think maybe they shouldn't have been taking, like one of the weight-loss products," says Haller. "Why tell your doctor if year doctor didn't know you were taking it?"

What's more, people may not make the connection between a bad reaction and a "natural" supplement. And even it people call the consumer complaint number that's on the product label, "manufacturers sometimes don't do anything with those complaints," says Haller.

* Troublesome interactions. "There's competition in the marketplace now to give consumers the most for their dollar by offering combinations of herbs and other ingredients," says Haller. "But combining ingredients, especially herbs, isn't a good idea, because we really don't understand a lot about how they interact."

In their analysis of calls to poison control centers in the U.S., Haller and her colleagues found that multiple-ingredient supplements were more likely than single-ingredient ones to produce severe adverse effects.

* No required warnings. "About two-thirds of the U.S. public believes that the government requires the labels of dietary supplements to include warnings about potential side effects or dangers," says Nancy Wong of the Harris Poll.