One group claims that six dietary supplements sold by Herbalife Ltd. contain high levels of lead if taken as directed, Reuters is reporting.

The Fraud Discovery Institute posted a letter on its Web site claiming that the supplements in question contain levels of lead that are dangerous and in excess of what California law allows under its Safe Drinking and Toxic Environment Act of 1994, also known as Prop. 65.

Herbalife told Reuters its products met with regulatory requirements in all of its markets.

"The FDA hasn't established a general limit on lead in foods, but we are certainly well within their suggested guidelines," Herbalife spokesman George Fischer said in a telephone interview, in which he was referring to the U.S. Food and Drug Administration, which sets dietary guidelines.

The six products mentioned in the letter on the Fraud Discovery Institute Web site all contain between two to 12 times the maximum amount of lead allowed in California's Prop. 65 law when taken as directed. They are the ShapeWorks Protein Drink Mix, Healthy Meal Nutritional Shake Mix, Tang Kuei Plus herbal tablets, Thermojetics Nature's Raw Guarana instant tea mix, ShapeWorks Cell Activator and Multivitamin Complex.

Dr. Mike Rosen, a board certified internist on Long Island, N.Y., said even if the products contain two to 12 times the maximum amount of lead allowed in a product, the law was designed with a large cushion.

"It's probably not a significant amount of lead; California made the cushion 1/1,000 of what a safe dose would be," Rosen said. "But, there is so much of this stuff on the market that is notoriously mislabeled. And, anyone can make their own product. You need to be cautious, and you need to discuss what you are taking with your health care provider."

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