The content of the red yeast rice supplement that manufacturers claim reduces cholesterol, varies dramatically depending on the brand, with some products containing far less of the active ingredient than has been shown scientifically to be effective, and other containing one or more contaminants, new analysis by ConsumerLab demonstrates.
Four out of the 10 products ConsumerLab tested contained a toxic substance called citrinin. "Our research indicates that consumers need to be very careful when choosing red yeast rice products, because we found a 100-fold variation in the amount of active compounds across the products," Dr Tod Cooperman, the president of the White Plains, New York-based independent testing company, told Reuters Health.
Red yeast rice is produced by fermenting yeast with rice, and contains lovastatin, the active ingredient in the prescription drug Mevacor, a member of the class of drugs known as statins used to treat high cholesterol. Studies have shown that red yeast rice may be effective in lowering low-density lipoprotein (LDL), or "bad" cholesterol. However, comparisons can not be made because of the differences in the compound. The Food and Drug Administration have no control over herbal products, which don't have to reveal how much lovastatin they contain.
ConsumerLab checked the lovastatin content of 10 red yeast rice products, and also checked for contamination with citrinin, which can be produced in the fermentation process. This substance is known to be toxic in animals, and may also be harmful to humans.