Wednesday, December 23, 2009

Red Yeast Rice


Red yeast rice is traditional Chinese “spice” used to flavor and color food such as Peking duck. The red yeast (Monascus purpureus) is grown on white rice and then fermented – creating the product known as “red yeast rice.” The yeast is then inactivated and the rice/yeast mixture is powdered. In traditional Chinese medicine (TCM), red yeast rice is used for “healthy blood” and to “strengthen the heart” while modern dietary supplements use red yeast rice (RYR) to lower cholesterol levels. In many Asian countries, total daily RYR consumption from foods ranges from 10-50 grams per day, while Western use as a dietary supplement is more in the range of 1-3 grams per day.

The modern-day use of RYR as a dietary supplement is for reducing cholesterol levels. Although the FDA has banned the sale of RYR as a dietary supplement (considering it an “unapproved drug” because of the presence of naturally occurring lovastatin), there are many examples of RYR products that remain on the market.

Red yeast rice contains a number of naturally occurring compounds known as monacolins – including monocolin K, also known as mevinolin or lovastatin. Monacolins are known to inhibit the activity of an enzyme in the liver (HMG-CoA reductase) which is needed to produce cholesterol. RYR also contains a mix of sterols (sitosterol, campesterol, and stigmasterol), isoflavones and unsaturated fatty acids, which are though to contribute to the cholesterol and lipid-lowering effects of the monacolins. Of the dozen or so monacolins found in RYR, one of them, monacolin K, is also known as lovastatin and is synthesized and marketed by the pharmaceutical company, Merck, as Mevacor® for reducing elevated cholesterol and triglyceride levels. Although the precise mechanism of action for RYR is not completely understood, the activity of the monacolins on reducing cholesterol synthesis does not appear to be sufficient to account for the entire effect observed in studies of RYR supplementation. For example, the dose of total monacolins reported in clinical trials of RYR supplementation is 9.6-13.5mg per day – while the recommended dose lovastatin is 20mg – suggesting that the cholesterol-lowering effects of RYR may be due to the combined actions of monacolins and other constituents such as sterols and fatty acids (possibly by simultaneously reducing cholesterol synthesis and absorption, while also promoting cholesterol excretion).


Historically, red yeast rice was used in China to make rice wine and preserve food. As a medicinal agent, traditional Chineses medicine practitioners use RYR to “promote blood circulation” and as a general aid to heart health. As a dietary supplement, RYR has been promoted as an alternative to cholesterol-lowering medications. However, in May of 1998, the FDA declared red yeast rice dietary supplements to be “unapproved drugs” under the terms of the Federal Food, Drug and Cosmetic Act and in March of 2001, a Federal Appeals Court supported the FDA’s position that RYR products should be removed from the market (though many examples exist of RYR-containing products that exist on the US market).

As a natural approach to controlling moderately elevated cholesterol levels (between 200-240mg/dL), red yeast rice supplements appear to be a safe and effective addition to a prudent diet and exercise regimen. For individuals with cholesterol levels well below 200mg/dl, RYR supplements probably do not justify the cost ($1-$1.50 per day), while individuals with cholesterol levels above 240mg/dL should consult with their personal physician to discuss the appropriateness of prescription medications for lowering cholesterol levels.

Scientific Support

Red yeast rice contains hydroxy-methyl-glutaryl (HMG) coenzyme reductase inhibitors, primarily lovastatin, and large amounts of unsaturated fatty acids that include monounsaturated fatty acids, diene-, triene-, tetraene-, and pentaene-fatty acids. Red yeast rice contains monacolin K (lovastatin, mevinolin), an HMG-CoA reductase inhibitor, which may contribute to its cholesterol-lowering effects.

Animal studies (mostly in rabbits) have clearly shown that consumption of red yeast rice reduces total and LDL cholesterol levels by 40-60% and triglyceride levels by 50-60%. The animal studies have also shown that RYR can inhibit the formation of atherosclerotic plaques. Several human studies have also shown the benefits of RYR in reducing elevated cholesterol and correcting dyslipidemia. In one study of subjects with elevated cholesterol levels (avg. 230mg/dL), 1.2 grams of RYR per day (13.5mg total monacolins) reduced total cholesterol by 23%, LDL by 31% and triglycerides by 34%, while HDL was elevated by 20%, following 8 weeks of supplementation (Keithley et al., 2002). In another study, subjects with elevated cholesterol were given RYR (10-13mg total monacolins) and showed a 20-36% reduction in cholesterol and triglyceride levels (Heber et al., 1999). A recent study used a combination of diet (American Heart Association Step 1 Diet) with RYR supplements and found that a 2-month course of RYR supplements (2.4 grams per day, containing 9.6mg total monacolins) reduced total cholesterol by 16%, LDL by 21% and total triglyceride levels by 25%, while HDL levels increase by 15% (Rippe et al., 1999). Discontinuation of RYR supplements following the treatment led to a rapid return of serum lipids to pre-study levels – despite adherence of the subjects to the American Heart Association step I diet.


In both animal and human studies, red yeast rice appears to be quite safe as a dietary supplement. No serious side effects have been reported in human trials, though mild gastrointestinal symptoms are possible. It is important to note that some potentially serious adverse side effects have been noted for prescription “statin” medications (muscle pain and damage with flu-like symptoms). Although such side effects have not been noted in published studies on RYR, some supplement manufacturers err on the side of caution and post a warning label on their products to alert consumers to the possibility. Because of the likely mechanism of action of monacolins in the liver, it is not recommended to exceed the recommended amount (see below), nor should RYR be taken by pregnant or lactating women or those individuals with liver disease.

Doses of 1.2-2.4 grams per day of red yeast rice (9.6-13.5mg of total monacolins) have been used to effectively reduce elevated cholesterol and triglyceride levels in several clinical trials. Because HMG-CoA reductase inhibitors, including the naturally-occurring lovastatin and other monocolins found in RYR may cause liver damage and myopathy, levels of cholesterol (every 4-8 weeks), liver function (every 6 weeks for 3 months and then every 6 months), and creatine phosphokinase (every 8 weeks or in presence of muscle pain or weakness) should be obtained on a routine basis. Also, because f the well-described reduction of Coenzyme Q10 levels in patients taking HMG CoA reductase inhibiting medications (“statins”), those taking RYR supplements may also benefit from a daily supplement of CoQ10.


1.Havel R. Dietary supplement or drug? The case of cholestin. Am J Clin Nutr. 1999;69:175-176.

2.Heber D, Yip I, Ashely JM et al. Cholesterol-lowering effects of a proprietary Chinese red-yeast-rice dietary supplement. Am J Clin Nutr 1999; 69(2): 231-36.

3.Heber D. Dietary supplement or drugs? The case for cholestin. Am J Clin Nutr. 1999;70:106-108.

4.Heber D. Reply to EG Bliznakov. Am J Clin Nutr. 2000;71:153-4.

5.Keithley JK, Swanson B, Sha BE, et al. A pilot study of the safety and efficacy of cholestin in treating HIV-related dyslipidemia. Nutrition 2002; 18: 201-4.

6.Li CL, Zhu Y, Wang Y, et al. Monascus purpureus-fermented rice (red yeast rice): a natural food product that lowers blood cholesterol in animal models of hypercholesterolemia. Nutr Res. 1998;18:71-81.

7.Qin S, Zhang W, Qi P, et al. Elderly patients with primary hyperlipidemia benefited from treatment with a Monascus purpureus rice preparation: a placebo-control, double-blind clinical trial. 39th Annual Conference on Cardiovascular Disease Epidemiology and Prevention. Orlando, Florida. March 25, 1999.

8.Rippe J, Bonovich K, Colfer H, et al. A multicenter, self-controlled study of Cholestin in subjects with elevated cholesterol. 39th Annual Conference on Cardiovascular Disease Epidemiology and Prevention. Orlando, Florida. March 25, 1999.

9.Wang J, Lu Z, Chi J et al. Multicenter clinical trial of serum lipid-lowering effects of a Monascus purpureus (red yeast) rice preparation from traditional Chinese medicine. Curr Ther Res 1997; 58(12): 964-78.

EDITOR'S NOTE: This monograph can be found in The Health Professional's Guide to Dietary Supplements (Lippincott, Williams & Wilkins) by Shawn M. Talbott, PhD and Kerry Hughes, MS.

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