Red Yeast Rice and Cholesterol

Red yeast rice (RYR) is a dietary supplement that has been marketed as a non-prescription product for lowering cholesterol.

RYR has been used in China for centuries both in cooking and to treat circulatory and digestive disorders. However, since it's been used in the U.S. for a much shorter period of time, it has generated significant controversy.

man looking at supplement bottle in store
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What Is Red Yeast Rice?

RYR is a rice product made by fermenting rice with the mold Monascus purpureus. It contains several substances that may reduce cholesterol levels, including beta-sterols, monounsaturated fatty acids, and a statin. The chemical name of the statin that exists in RYR is monacolin K, but it is known better in the U.S. as lovastatin (marketed as Mevacor).

Does RYR Lower Cholesterol?

Studies have demonstrated that RYR, as traditionally produced in China and as originally sold as a dietary supplement in the U.S., does indeed reduce LDL cholesterol levels.

For instance, one study found that taking RYR daily can reduce low-density lipoprotein (LDL) levels between 15% and 25% in a timeframe of six to eight weeks. 

The Controversy

The controversy, of course, is that RYR contains a naturally generated statin. Statins, according to law, are drugs and therefore are subject to regulation.

The controversy began in 1999, shortly after clinical trials first showed that RYR could indeed significantly lower cholesterol levels. At that time the FDA ruled that RYR containing monacolin K was a drug, and thus ordered it removed it from the shelves. Lawsuits ensued, and (after several back-and-forth rulings) the 10th U.S. Circuit Court of Appeals agreed with the FDA.

So, in the U.S., RYR can still be sold legally, but only if steps are taken in its manufacturing process to remove the monacolin K.

RYR is still available as a dietary supplement, and it is produced by several manufacturers. As a dietary supplement, its formulation and content are still not strictly regulated. It is very difficult if not impossible to find out what a particular RYR product sitting on a shelf does contain.


In the face of all this confusion, two clinical trials appeared showing that even in the post-FDA period, at least some RYR available in the U.S. is effective in reducing cholesterol levels.

In 2009, a study from Pennsylvania showed that in 60 patients who had to stop taking statin drugs because of statin-induced muscle pain, taking RYR and initiating lifestyle changes for 24 weeks significantly reduced LDL cholesterol levels by 43 mg/dL from baseline at the 12-week mark, and by 35 mg/dL at the 24-week mark, compared to taking a placebo and making the same lifestyle changes. Reductions in total cholesterol were also seen.

And in 2010, investigators from the University of Pennsylvania reported that in patients who had to stop taking statins due to muscle pain, RYR was just as effective as 20 mg per day of the statin drug pravastatin (Pravachol) in reducing cholesterol levels. (Both RYR and Pravachol produced only a very low incidence of recurrent muscle pain.)

In the 2009 study, the investigators performed a formal chemical analysis on the RYR product they used in their study (from Sylvan Bioproducts in Kittanning, Pennsylvania). They found that the RYR still contained monacolin K as well as eight other monacolins.

The result of this chemical analysis suggests two things. First, at least some RYR available in the U.S. apparently still contains at least some lovastatin, and second, even if all the lovastatin were completely removed, other similar chemicals in RYR (which the FDA has not yet specifically restricted) may be effective in reducing cholesterol.

Should You Take RYR?

On the surface at least, taking RYR would seem to be at least a reasonable consideration if you are looking for a non-prescription means of cholesterol lowering. However, what you would really be doing is taking variable and unknown amounts of certain statin-like substances. It is impossible to tell, from manufacturer to manufacturer, or even from bottle to bottle, what you are really buying.

If you want to reduce your cholesterol without losing your shirt to the big drug companies, ask your healthcare provider about generic statin drugs. They're readily available, cheap (perhaps even cheaper than RYR), and as a bonus, the dosage you’re getting will actually be known, and can be controlled and adjusted to optimize your results.

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