Manufacturers don’t report quantities of active ingredients, which can be next to nil, or the presence of fungal toxins

By Janet Raloff

Web edition: October 26, 2010

A little more than a decade ago, a federal court ruled that over-the-counter red-yeast rice products were not drugs — despite the fact that these products contained naturally occurring chemicals that were functionally indistinguishable from lovastatin, a cholesterol-lowering prescription drug. And so a major dietary supplement industry was born. By 2008, Americans were spending $20 million a year on red-yeast rice products, many on their doctor’s recommendation (and perhaps even via their doctor’s offices).

But a new study warns that not all red-yeast rice products contain pharmacologically active concentrations of the fungal products. As such, its authors caution: “Buyer Beware!”

Early research on red-yeast rice — an old Chinese herbal remedy — was conducted by Pharmanex of Simi Valley, Calif., on a product that it called Cholestin. Owing to the red yeast’s name, Monascus purpureus, the product’s cholesterol-lowering constituents were named monacolins. Of particular interest was the yeast’s production of monacolin K, which is equivalent to lovastatin.

In several published studies, Cholestin and a few knock-offs performed as claimed.

But that didn’t make the Food and Drug Administration happy. It argued that by containing what was essentially nature-made lovastatin, such products constituted drugs warranting regulation. To bypass such government controls, “red-yeast rice manufacturers typically do not disclose levels of lovastatin or other monacolins in their products, and there is no standardization of these levels across manufacturers,” report cardiologist Ram Gordon of the University of Pennsylvania Health System and his colleagues.

So they decided to investigate for themselves, assaying monacolin concentrations in a dozen commercial red-yeast rice products. Their findings appear in the October 25 issue of the Archives of Internal Medicine.

At the extremes: One product contained less than a third of a milligram of total monacolins, another hosted more than 11 milligrams per capsule. And what about the lovastatin surrogate? One brand of capsules contained a tenth of a milligram per dose, while another brand had 100 times as much.

Especially concerning: The researchers tested for — and found — citrinin, a potentially kidney-poisoning fungal toxin, in a third of the brands.

Although Gordon’s team identifies the products that it tested, it doesn’t identify how the particular brands fared. So we learn only that brand “F”, the worst of the bunch, is virtually devoid of monacolins (especially the lovastatin type) and the richest source of citrinin (at 114 picograms per capsule). Meanwhile, brand “H” not only topped the charts in monacolins but also was citrinin-free.

In theory, Gordon’s group would have performed a bigger service by letting us know which brands best modeled a cholesterol-lowering agent and which were pointless — if not outright dangerous. Then again, as I noted several years ago in a cover story titled “Herbal lottery,” (SN: 6/7/03, p. 359) it’s devilishly difficult to standardize herbal remedies because they are, well, botanicals (or their fungal equivalents). As such, their constituents vary with the season, their nutrients, horticultural conditions — even the presence of any pests or parasites. So a red-yeast rice product grown in one facility could vary from that produced elsewhere, or even from batches produced a week earlier or later.

By the way, Cholestin was not among products tested in the new study. Pharmanex, which has since been bought by Nu Skin, still markets a Cholestin. However, Gordon’s group notes, when FDA ruled that monacolins constituted an unapproved drug, Pharmanex removed red-yeast rice from its product line.