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Red Yeast


What other names is Red Yeast known by?

Arroz de Levadura Roja, Cholestin, Hong Qu, Koji Rouge, Levure de Riz Rouge, Monascus, Monascus purpureus, Monascus Purpureus Went, Red Rice, Red Rice Yeast, Red Yeast Rice, Red Yeast Rice Extract, Riz Rouge, Xue Zhi Kang, XueZhiKang, XZK, Zhibituo, Zhi Tai.

What is Red Yeast?

Red yeast is the product of rice fermented with Monascus purpureus yeast. Red yeast supplements are different from red yeast rice sold in Chinese grocery stores. People use red yeast as medicine.

Red yeast is used for maintaining desirable cholesterol levels in healthy people, reducing cholesterol in people with high cholesterol, for indigestion, diarrhea, improving blood circulation, and for spleen and stomach health.

In foods, red yeast is used as a food coloring for Peking duck.

The active ingredient in red yeast is the same as the active ingredient in prescription drugs called statins used for high cholesterol. That's why red yeast has all the possible side effects, drug interactions, and precautions associated with this type of drug. The American Heart Association warns against using red yeast until the results of long-term studies are in. You should talk with your healthcare provider if you plan to take red yeast.

You may have come across a red yeast product called Cholestin, manufactured by Pharmanex. It was one of the most widely studied red yeast products. Originally, Cholestin contained the same active ingredient found in statin drugs. This caused the U.S. Food and Drug Administration (FDA) to call Cholestin an unapproved drug. Cholestin was reformulated so that its active ingredient is now something else.

Likely Effective for...

  • High cholesterol. Some research shows that taking a specific red yeast product for up to 6 months can lower total cholesterol, low-density lipoprotein (LDL or "bad") cholesterol levels and triglycerides. However, this specific product contains large amounts of a chemical similar to "statin" drugs, such as lovastatin. Statins are approved by the FDA to lower cholesterol. In the U.S., the Food and Drug Administration (FDA) now considers this product and other red yeast products that contain statins to be illegal unapproved drugs. However, outside the U.S., these specific red yeast products are still available. Some red yeast products available in the U.S. these days contain little or no statins. It is not known if these products do much to reduce cholesterol levels in people with high cholesterol. Some other products still contain significant amounts of statins. One analysis shows that that some of these products can contain up to 5 mg of statins per tablet.

Possibly Effective for...

  • Heart disease. Taking 0.6-1.2 grams of red yeast rice daily for an average of 4.5 years decreases total cholesterol, low-density lipoprotein (LDL or "bad") cholesterol, and triglycerides. It also decreases the risk of heart disease-related events, heart attacks, and death in people with a history of heart attack.
  • High cholesterol and triglyceride levels caused by human immunodeficiency virus (HIV) disease (AIDS). Taking red yeast rice by mouth seems to reduce cholesterol and triglyceride levels in people with abnormal levels associated with HIV infection.

Possibly Ineffective for...

Insufficient Evidence to Rate Effectiveness for...

  • Diabetes. Some early research shows that taking 600 mg of red yeast daily for 8 weeks can lower total cholesterol, triglycerides, and blood sugar in people with diabetes. Other research shows that taking 1.2 grams of red yeast rice daily for 12 weeks reduces low-density lipoprotein (LDL or "bad") cholesterol and triglycerides, as well as increases high-density lipoprotein (HDL or "good") cholesterol in people with diabetes and liver disease.
  • Liver disease. Some research shows that taking 1.2 grams of red yeast rice daily for 12 weeks reduces levels of liver enzymes associated with liver damage and improves blood thickness in people with diabetes and a certain type of liver disease.
  • Indigestion.
  • Diarrhea.
  • Improving blood circulation.
  • Spleen and stomach problems.
  • Other conditions.
More evidence is needed to rate the effectiveness of red yeast for these uses.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).

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