Natural Standard® Patient Monograph, Copyright © 2017 ( All Rights Reserved. Commercial distribution prohibited. This monograph is intended for informational purposes only, and should not be interpreted as specific medical advice. You should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.


Red yeast rice (RYR) is made from yeast (Monascuspurpureus) grown on rice. It is a dietary staple in some Asian countries. Processed red yeast rice supplements include red yeast rice extract (RYRE), which is any extract of red yeast rice, and Xuezhikang, an alcohol extract of red yeast rice.

RYR contains several compounds known as monacolins, which block the production of cholesterol. One of these, monacolin K, has the same structure as the drugs lovastatin and mevinolin. Studies suggest that RYR use may lead to a 10-33% reduction in low-density lipoprotein (LDL, or "bad") cholesterol. This is a moderate effect, compared to the U.S. Food and Drug Administration (FDA)-approved "statin" drugs. Information on the long-term safety of RYR is limited at this time.

RYR extract (RYRE) has been sold in over-the-counter supplements to lower cholesterol, in the form of products such as Cholestin® (Pharmanex, Inc.). However, the formula has been changed. Cholestin® contains many compounds in addition to monacolin K, including other monacolins, starch, fiber, protein, and fatty acids. Research suggests that this product may treat high cholesterol and triglycerides in both humans and animals. Some studies report that RYR use may increase levels of high-density lipoprotein (HDL, or "good") cholesterol. However, information on the effects of monacolin K alone is lacking.

There has been some controversy between Pharmanex, Inc., the FDA, and statin manufacturers as to whether Cholestin® should be considered a drug or a dietary supplement. The U.S. District Court in Utah ruling in March 2001 states that RYRE is an unapproved drug. Thus, the RYRE known as Cholestin® is no longer available in the United States. Other products containing RYRE alone or in combination products may still be commercially available in the United States, primarily through Internet retailers.

Besides RYR's use for high cholesterol, pigments made by Monascus species have been used to color food in Asian cooking. Future uses of RYR may include decreasing heart disease risk and improving the health of people with diabetes.

This evidence-based monograph was prepared by The Natural Standard Research Collaboration