How Does A Doctor Critically Review A Healthcare Product?

Medical Author: Dennis Lee, M.D.

A Traditional Chinese Herb Lowers Cholesterol?

Many viewers have e-mailed us questions regarding alternative medicine and herbal medicine products. doctors recognize the importance of these topics and are organizing proper resources to address them. Meanwhile, it is important that viewers understand's publishing philosophy and priority.'s first priority is to present information that has withstood critical review by expert physicians. Our goal is to do more than just report information. We aim to interpret information and place it in proper perspective for our viewers. To conduct a "critical review" of a healthcare product, we ask the following questions:

  1. How does the product work?
  2. Have animal studies been done?
  3. Have human studies (clinical trials) been conducted?
  4. Were these studies performed by reputable scientists using sound study designs and methodology?
  5. Were the results of these studies duplicated by other reputable scientists?
  6. What do the studies show about the short-term and long-term safety and efficacy of the product?
  7. How does the product compare with other products?
  8. What patients are most likely to benefit from the product

Let us now apply these questions to red yeast rice.

Red yeast rice is rice that has been fermented by a strain of red yeast. The Chinese have used it for many centuries as a food preservative (to prevent meat spoilage) and as an ingredient in rice wine. It is responsible for the red color of Peking duck. Red yeast rice also has been used as a medicine in China for over 1,000 years for improving blood circulation and for alleviating indigestion and diarrhea. Recently, doctors in China have been using red yeast rice to lower blood cholesterol and triglycerides.

How does this product work?

In 1977, Professor Endo in Japan discovered a natural cholesterol-lowering substance that is produced by a strain of yeast. This substance lowers cholesterol by inhibiting HMG-CoA reductase, an enzyme that is important in regulating the production of cholesterol in the body. Professor Endo named this substance moncacolin K. Monacolin K, in fact, is lovastatin, the active ingredient in the popular cholesterol-lowering statin drug, Mevacor™. It turns out that red yeast rice also contains Monacolin K plus several chemically similar compounds.

What about animal and human studies?

Chinese scientists conducted most of the animal and human studies on red yeast rice. The results of some 17 studies involving approximately 900 Chinese subjects with modestly elevated cholesterol levels have been published. These studies consistently showed that specially chosen red yeast rice preparations lower total cholesterol (by an average of 10-30%), lower LDL cholesterol (by an average of 10-20%), lower triglycerides (by an average of 15-25%), and increase HDL (by an average of 7-15%). Additionally, animal studies using specially chosen red yeast rice demonstrated no toxicity.

Were the results of these studies duplicated by other reputable scientists?

Scientists at the UCLA Center for Human Nutrition chemically analyzed and verified the active ingredients in a red yeast rice product sold under the name Cholestin™ . They then conducted a placebo-controlled trial involving 83 American adults with borderline-high to moderately elevated cholesterol. They found that Cholestin™ reduced total cholesterol, LDL cholesterol, and triglyceride levels but had no effect on HDL cholesterol. This study was published in the American Journal of Clinical Nutrition (1999; 69:231-7).

What are this product's side effects?

Human trials in China and in the United States reported only rare and minor side effects of heartburn or indigestion with red yeast rice. No liver, kidney, or muscle toxicity has been reported in the published literature.

How does this product compare with other products?

Statin drugs such as Mevacor, Pravachol, Zocor have been shown in numerous multi-year, large-scale clinical trials to be safe and effective in lowering LDL cholesterol and in decreasing the risk of first first and second heart attacks. Red yeast rice is probably as effective in lowering LDL cholesterol as a low dose statin drug. Although the statin drugs are generally safe and well tolerated, they still may rarely cause liver and muscle damage. There are no published reports of liver or muscle damage with red yeast rice. However, red yeast rice has not been as extensively studied as the statin drugs. Thus, conclusive proof of its long-term safety will have to await further data (after more people have used it or long-term, large-scale clinical trials have been done).