FDA Assails Claims About Vitamins and Dietary Aids : Health: Agency study says product labeling in many cases is unproven and potentially dangerous. Probe is examining need for regulatory action.

Americans are being subjected daily to unproven and potentially dangerous health claims made by dietary supplements, the Food and Drug Administration said in a study released Thursday.

The agency cited more than 500 examples of fraudulent claims about vitamins and other dietary supplements--including mineral, herbal and ammino acid products.

“When consumers see a health claim for a dietary supplement, they assume it will provide the benefit it touts,” FDA Commissioner David A. Kessler told a congressional hearing Thursday. “In fact, the marketplace is awash in unsubstantiated claims.”

The FDA examined materials such as pamphlets, brochures and advertisements--and also dispatched personnel from each of its 21 field offices across the nation into local stores to pose as consumers seeking information about the products.

Kessler, testifying before the health and environment subcommittee of the House Energy and Commerce Committee, said that the investigation was launched in part to document the need for controversial regulations proposed by the agency that would require supplement manufacturers to back up health claims with scientific evidence.

If enacted, the regulations would hold the dietary supplement industry to the same standards that the FDA has set for health claims about food--and would mean that scientific experts must agree about the value of a supplement before the manufacturer may place the information on a label.

The supplement industry has maintained consistently that it has not made fraudulent claims and has accused the FDA of being overly stringent in trying to control the flow of information to the public.

“Both the FDA and the industry owe it to consumers to make sure that the information they receive is truthful and to disclose the level of science that is behind a claim. But it is not appropriate for the FDA to conduct the equivalent of book-burnings and intellectual lynchings,” Martie Whittekin, president of the National Nutritional Foods Assn., told the subcommittee.

Rep. Henry A. Waxman (D-Los Angeles), chairman of the subcommittee, said that at least three bills--two in the House and one in the Senate--have been introduced in Congress to attempt to regulate the $4-billion-a-year industry. An estimated 60 million Americans use dietary supplements daily and as many as 100 million use them occasionally, Waxman said.

A growing body of research continues to indicate that some vitamins--particularly the antioxidant Vitamins C, E and beta carotene, a form of Vitamin A--can play a role in preventing heart disease, certain kinds of cancer and other conditions.

However, most of the studies remain inconclusive.

The FDA report listed nine herbal substances, two amino acids and four vitamins and minerals that it said can be toxic at high doses. For example, the report said, the amino acid L-tryptophan has been associated with a connective tissue disease blamed for 1,500 cases and 38 deaths.

The regulations that have been proposed by the FDA were required by the Nutrition Labeling and Education Act, which was enacted by Congress in 1990 to overhaul the nation’s food labels. But some pending legislation attempts to weaken the dietary supplement standards.

The FDA report released Thursday lists hundreds of dietary supplements that claim to cure, treat or reduce the risk of a range of health problems, some minor, others as life-threatening as AIDS and cancer.

“These claims appear in current catalogues, brochures and other advertising materials, or, in some cases, on the product label,” Kessler said. “They are also being made by some salespeople at health food stores--93% of the health food stores, when we asked, recommended dietary supplements for cancer, to fight infection and to treat high blood pressure.”