Red Yeast Rice

This substance, native to China, is a fermentation by-product of cooked non-glutinous rice on which red yeast has been grown.¹ The dried, powdered red yeast rice is used medicinally.

Since 800 A.D., red yeast rice has been employed by the Chinese as both a food and a medicinal agent. Its therapeutic benefits as both a promoter of blood circulation and a digestive stimulant were first noted in the traditional Chinese pharmacopoeia, Ben Cao Gang Mu-Dan Shi Bu Yi, during the Ming Dynasty (1368–1644).² Practitioners of Traditional Chinese Medicine use red yeast rice to treat abdominal pain due to stagnant blood and dysentery, as well as external and internal trauma.³ In addition to its therapeutic applications, red yeast rice has been used for centuries as a flavor enhancer, a food preservative, and a base for a Taiwanese alcoholic rice-wine beverage.^{4, 5}

In addition to rice starch, protein, fiber, sterols, and fatty acids, red yeast rice contains numerous active constituents, including monacolin K, dihydromonacolin, and monacolin I to VI.

Researchers have determined that one of the ingredients in red yeast rice, called monacolin K, inhibits the production of cholesterol by stopping the action of a key enzyme in the liver (e.g., HMG-CoA reductase) that is responsible for manufacturing cholesterol.⁶ The drug lovastatin (Mevacor®) acts in a similar fashion to this red yeast rice ingredient. However, the amount per volume of monacolin K in red yeast rice is small (0.2% per 5 mg) when compared to the 20–40 mg of lovastatin available as a prescription drug.⁷ This has prompted researchers to suggest that red yeast rice may have other ingredients, such as sterols, that might also contribute to lowering cholesterol.

Along with its evaluation in animal trials,⁸ red yeast rice has been clinically investigated as a therapy for reducing cholesterol in two human trials. In one trial, both men and women taking 1.2 grams (approximately 13.5 mg total monacolins) of a concentrated red yeast rice extract per day for two months had significant decreases in serum cholesterol levels.⁹ In addition, people taking red yeast rice had a significant increase in HDL (“good”) cholesterol and a decrease in LDL (“bad”) cholesterol. Elevated triglycerides were also found to be lowered.

A double-blind trial at the UCLA School of Medicine determined that red yeast rice in the amount of 2.4 grams per day (approximately 10 mg total monacolins) in capsules significantly decreased total- and LDL-cholesterol levels in a sample of people with elevated cholesterol after 12 weeks of therapy. Triglycerides were also reduced in those taking red yeast rice. However, unlike the original study, HDL values did not increase substantially.¹⁰

The red yeast rice used in various studies was a proprietary product called Cholestin®, which contains ten different monacolins. The amount of Cholestin used in these studies was 1.2–2.4 grams (5–10 mg of monacolins) per day in divided amounts for 8-12 weeks.^{11, 12}

Note: Cholestin has been banned in the United States, as a result of a lawsuit alleging patent infringement.

Other red yeast rice products currently on the market differ from Cholestin in their chemical makeup. None contain the full complement of ten monacolin compounds that are present in Cholestin, and some contain a potentially toxic fermentation product called citrinin.¹³ Despite these concerns, other red yeast rice products are being widely used and anecdotal reports suggest that they have a similar safety and efficacy profile as that of Cholestin.

As in the case of medications that inhibit HMG-CoA, it is advisable that people using red yeast rice products also supplement 30–60 mg of coenzyme Q10 daily.

The Cholestin brand of red yeast rice has been generally well tolerated with possible temporary mild side effects such as heartburn, gas, and dizziness.¹⁴ This product should not be used by people with liver disorders¹⁵ and its safety during pregnancy has not been established.

There is one case report of muscle weakness and joint pain occurring in a man who was taking red yeast rice.¹⁶ Because the man was also taking several prescription drugs, it was not clear whether the symptoms were caused by red yeast rice. In another case report, a woman developed severe muscle pain with laboratory evidence of muscle damage while taking red yeast rice. In that case, red yeast rice appeared to be the cause of the muscle damage.¹⁷ These reports should be taken seriously, because muscle problems are common side effects of prescription HMG CoA-reductase inhibitors (statins). However, the frequency of side effects with red yeast rice is substantially lower than with statin drugs.¹⁸

There is one case report of hepatitis developing in a woman taking red yeast rice. She was also taking two medications that have been reported to cause hepatitis, so a cause-effect relationship with red yeast rice was not proven. However, since statin drugs have been reported to cause hepatitis, it is possible that this complication can also result from taking red yeast rice.¹⁹