Bottom Line: Red yeast rice appears to lower blood cholesterol and triglyceride levels with few side effects, but there is no evidence that red yeast rice can treat cancer. Persons with liver disease, and pregnant women should not use red yeast rice.
Little is known about the way red yeast rice works. One of its constituents, monacolin K, also known as lovastatin is an active ingredient in the cholesterol-lowering drug, Mevacor®. The drug works by inhibiting an enzyme essential for the creation of cholesterol in the body; therefore it is assumed that red yeast rice works through a similar mechanism.
High Cholesterol: 502 patients with high cholesterol took part in a study of red yeast rice in China. 324 patients received a preparation of red yeast rice and 122 patients received another Chinese herbal medicine. After eight weeks, patients who received the red yeast rice preparation had lower total cholesterol, triglycerides and LDL ("bad") cholesterol and higher HDL ("good") cholesterol levels. There were few reported side effects. While this study seems to show the red yeast rice can help patients with high cholesterol, a few facts weaken this study. First of all, the researchers left out the results of 10% of the patients in the trial without any stated reason. Secondly, the size of the control group and the choice of the control treatment is questionable. Better designed studies are necessary to corroborate these finidings.
Another group of researchers studied 83 subjects with high cholesterol for twelve weeks. Subjects were randomized to receive either 2.4 grams of red yeast rice per day or placebo. Both groups also consumed a diet where total fat, calories and cholesterol were limited to levels comparable with the American Heart Association Step 1 diet. The subjects taking the red yeast rice showed significant reductions in total and LDL cholesterol compared to the control group. The subjects who took the red yeast rice had no reported side effects.
Another group of researchers studied 14 subjects with high cholesterol as a result of HIV infection. Subjects were randomized to receive either 2.4 grams Cholestin™ daily or placebo for eight weeks. Subjects treated with Cholestin™ had significant reduction in total cholesterol and LDL cholesterol when compared with the control group. No adverse effects were seen.
A 26-year-old man developed a severe allergic reaction to red yeast rice.
Persons with liver disease, and pregnant women should not use red yeast rice.
Citrinin, a toxic fermentation byproduct, has been found in a number of preparations of red yeast rice. Because this product is regulated by the FDA as a dietary supplement, it may not be manufactured or tested under standardized conditions. Extra caution should be taken in ensuring the quality of this product.
Grapefruit juice may increase the effect of red yeast rice.
Note: Lovastatin, an approved prescription drug, has been associated with muscle pain, tenderness and weakness. It is possible that red rice yeast may demonstrate similar side effects.
The U.S. Food and Drug Administration declared that the dietary supplement Cholestin, manufactured by Pharmanex, could not be marketed as a dietary supplement because it contained the same active ingredient as the approved prescription drug, Mevacor® (2).
Used in China as food and medicine for thousands of years, red yeast rice is the fermented product of the fungus, Monascus purpureus, grown on rice. It was first marketed as a dietary supplement in the United States by Pharmanex under the trade name Cholestin (1). The major active constituent, monacolin K, is the same as lovastatin, an active ingredient in the cholesterol-lowering drug, Mevacor® (2). A number of clinical trials have demonstrated effectiveness in using red yeast rice preparations for reducing cholesterol levels in hyperlipidemic patients (3)(4)(5)(14)(15)(16)(17). Tests of several preparations of red rice yeast revealed that many contained citrinin, a toxic fermentation byproduct (6). Adverse events include stomachache, heartburn, dizziness and flatulence (7). Lovastatin has been associated with muscle pain, tenderness and weakness, which theoretically may occur with red yeast rice. Persons with liver disease, pregnant women and persons under the age of eighteen should not use red yeast rice (1). A case of anaphylaxis in a 26-year-old man working with red yeast rice has also been reported (8).
Components such as citrinin, monacolines and monankarin, and monascopyridines have been isolated from red yeast rice (10). Fermentation products are standardized to contain 0.4% 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors. HMG-CoA reductase is the rate-limiting enzyme in endogenous cholesterol biosynthesis (1). The principal HMG-CoA reductase inhibitor is monacolin K, also known as lovastatin (11). Lovastatin is also an active ingredient in the cholesterol-lowering drug, Mevacor® (2).
Reported: stomachache (3), heartburn, dizziness and flatulence (7). Case: Anaphylaxis in a 26-year-old man cooking with red yeast rice has been reported (8). In addition, rhabdomyolysis in a 28-year-old renal transplant recipient has also been reported (12). Note: Lovastatin, an approved prescription drug, has been associated with muscle pain, tenderness and weakness. Theoretically, these conditions may also occur with red rice yeast (1).
Heber D, et al. Cholesterol-lowering effects of a proprietary Chinese red-yeast-rice dietary supplement. Am J Clin Nutr 1999 Feb;69(2):231-6. Eight-three subjects with hyperlipidemia participated in a 12-week randomized controlled trial of red yeast rice supplementation. Subjects were randomized into two treatment arms to receive either 2.4 grams per day of red yeast rice or placebo. Both groups also consumed a diet similar to the American Heart Association Step I diet. Total cholesterol and LDL cholesterol was significantly reduced in the treatment arm when compared to control after eight and 12 weeks. There were no reported side effects in the treatment arm. Keithley JK, Swanson B, Sha BE, Zeller JM, Kessler HA, Smith KY. A pilot study of the safety and efficacy of cholestin in treating HIV-related dyslipidemia. Nutrition 2002;18:201-4. 14 subjects with dyslipidemia related to HIV participated in a randomized controlled trial of Cholestin. Subjects were randomized to receive either 1.2 grams Cholestin twice daily or placebo for eight weeks. One subject dropped out of each group. Among those who completed the protocol, significant declines from baseline in mean for fasting total cholesterol after two and eight weeks and for LDL cholesterol after eight weeks were observed. No adverse effects were seen. Researchers suggest that larger and longer-term trials of his approach should be conducted to confirm results.
Wang J, et al. Multicenter clinical trial of the serum lipid-lowering effects of a Monascus purpureus (red yeast) rice preparation from traditional Chinese medicine. Current Therapeutic Research, Clinical & Experimental 1997 58(12):964-978.
