December 6, 2007
The Center for Science in the Public Interest is calling on the Food and Drug Administration to require manufacturers of dietary supplements that contain large doses of synthetic beta-carotene to warn smokers and people exposed to asbestos of an increased risk of lung cancer if they take the supplements.
"Though there is a lot of wishful thinking about antioxidants preventing cancer, the evidence connecting high-dosage beta-carotene supplements to increased rates of lung cancer in smokers is compelling," said CSPI senior nutritionist David Schardt.
CSPI says supplements with more than 5,000 IU, or 3 mg, should bear warning notices and that FDA should take enforcement action against companies that market the pills without the warnings.
Natures Made, Natures Bounty, Source Naturals, Vitamin Shoppe, GNC, and others market pills with 25,000 IU, or 15 mg, of beta-carotene. Most multivitamins have 5,000 or less IU of beta-carotene but a few have more and should also bear a warning for smokers, says CSPI.
"Obviously, quitting smoking is the most important thing one can do to avoid lung cancer. But smokers and former smokers alike should absolutely not take supplements containing high-potency synthetic beta-carotene. Warning labels would help drive that message home," Schardt said.
The Food and Nutrition Board of the Institute of Medicine, a panel of the National Institutes of Health, and the United Kingdoms Food Standards Agency have all separately determined that beta-carotene supplementation isnt necessary for the general population and is especially risky for smokers and the asbestos-exposed.
Last month, a major report on diet and cancer by the World Cancer Research Foundation and the American Institute for Cancer Research found that the evidence linking beta-carotene to cancer in smokers is convincing.
CSPIs letter says that for regulatory purposes, beta-carotene supplements with high levels of beta-carotene should be considered adulterated and misbranded, because lacking warning labels, they pose a significant risk to smokers.