Millions of people consume red yeast rice to lower their cholesterol levels. The dietary supplement contains monacolins, which are known to inhibit cholesterol synthesis in the liver. A purified version of one member of the monacolin family, monacolin K, is also known as lovastatin, the widely prescribed, highly effective cholesterol-lowering drug.
Studies of some (but not all) red yeast rice formulations have shown that they do in fact reduce blood levels of low-density lipoprotein (LDL, or “bad”) cholesterol, and reduce the risk of heart attacks and cardiovascular disease.
Does anybody have a problem with this?
Well, yes. The problem is that since red yeast rice products are classified as dietary supplements and not drugs, they are not regulated by the FDA and hence not always subjected to quality and safety checks that legit drugs get before hitting the shelves. With dietary supplements, you don’t know how much of the “good stuff” you’re getting, and you don’t know what else you may be getting with it.
Ram Gordon and colleagues at the University of Pennsylvania highlighted the problem in a recent study, which they published in the Archives of Internal Medicine. For their study, Gordon’s team asked an independent laboratory to measure monacolin levels in 12 commercially available formulations of red yeast rice. They also asked the lab to test for citrinin, a byproduct of fungal metabolism of red yeast rice, which is how monacolins are produced from rice in the first place.
Citrinin is toxic: it causes kidney damage, at least in animals.
The label on each formulation in Gordon’s study said it contained “600 mg capsules” of active product, yet Gordon’s team found that the total monacolins per capsule varied by more than 30-fold across the 12 preparations (lowest = 0.31 mg, highest = 11.15 mg). The range of monacolin K (a.k.a lovastatin) varied even more, by a remarkable 100 fold (lowest = 0.10, highest = 10.09 mg).
Four of the 12 products contained citrinin, in levels ranging from 24 parts per million to 189 parts per million.
Of interest, the average dose of lovastatin contained in the 12 red yeast rice formulations was 6 mg/day. The maximum dose was 14.5 mg/day. The normal dose of FDA-approved lovastatin is 10-80 mg/day.
“Our findings suggest the need for improved standardization of red yeast rice (RYR) products and product labeling. Until this occurs, physicians should be cautious in recommending RYR to their patients for the treatment of hyperlipidemia and primary and secondary prevention of cardiovascular disease,” the authors wrote.