Red Yeast Rice

Last Updated: January 4, 2024

Red yeast rice (RYR) is a fermented rice used traditionally in East Asia as a medicine and food. Supplementation with RYR seems to reduce cholesterol levels and may improve overall cardiovascular health. The main active compound in RYR is monacolin K, which is identical to the cholesterol-lowering medication lovastatin.

Red Yeast Rice is most often used for

What is red yeast rice?

Red yeast rice (RYR) is a fermented rice with a long history of use as a food and medicine in East Asia.[8] RYR is produced by fermenting white rice (Oryza sativa) with an edible fungus, most commonly Monascus purpureus, which results in the production of a variety of bioactive compounds and pigments, the latter of which imparts a reddish-purple color to the rice.[7] The primary active compound in RYR is thought to be monacolin K, which is structurally identical to the cholesterol-lowering medication lovastatin.[7] However, the type and amount of monacolins present in RYR can vary depending on the fermentation conditions and the type of yeast used.[9] The majority of research on RYR has examined its effects on dyslipidemia and general cardiovascular health, with promising results.

What are red yeast rice’s main benefits?

In clinical trials, RYR consistently demonstrates the ability to improve lipid profiles in people with dyslipidemia. RYR seems to reduce low-density lipoprotein (LDL) cholesterol, triglyercides, total cholesterol, and apolipoprotein B; it also seems to increase high-density lipoprotein (HDL) cholesterol.[5][10] Overall, RYR is thought to reduce LDL cholesterol by 15 to 25% within 6 to 8 weeks, and its effect on lipid profiles is comparable to moderate-intensity statin medications (first-line cholesterol-lowering medications).[11][5] RYR may improve markers of atherosclerosis and protect against major adverse cardiac events; however, most of this research has been conducted in Chinese populations, and its generalizability to other populations is not clearly established.[3][12][4] RYR may also reduce systemic inflammation, as suggested by reductions in C-reactive protein, although this effect is less thoroughly researched.[13][14][15]

What are red yeast rice’s main drawbacks?

RYR appears to be well-tolerated by most people, and generally, studies have not found differences in rates of side effects between RYR and placebo.[9][16] Despite this, several case reports have suggested that, on rare occasions, RYR supplementation at normal dosages (equivalent to 3–10 mg daily of monacolin K) may cause rhabdomyolysis (dangerous muscle breakdown) or hepatitis (liver inflammation).[17] Rhabdomyolysis is a known risk of treatment with prescription statin medications, including lovastatin, and is estimated to occur in 1 in every 10,000 people.[18][19] Hepatitis has also very rarely been observed with lovastatin treatment.[20] Additionally, RYR supplements can contain citrinin which is a potentially harmful compound produced during fermentation. Citrinin can be toxic to the liver and kidneys and care should be taken to choose an RYR supplement that is citrinin-free.[7]

Importantly, monacolin K is metabolized by cytochrome P450 3A4 (CYP3A4) enzymes. Medications or foods that inhibit CYP3A4 (e.g., verapamil, clarithromycin, ketoconazole, ritonavir, grapefruit) can lead to increased levels of monacolin K in the blood and this combination should be avoided.[9] Additionally, RYR should not be taken in addition to statin medications. This combination may increase the risk of serious side effects and isn’t likely to provide additional therapeutic benefits.[17][5]

Lastly, there is a concerning degree of variability in the content of monacolin K in RYR, and most supplements are not transparent about how much of this active compound they contain. For example, a study conducted in the United States found that the amount of monacolin K in 26 tested supplements differed up to 60-fold.[21] This could lead to inconsistencies in the effectiveness of RYR supplementation.

How does red yeast rice work?

RYR contains a variety of compounds with biological activity, but monacolins — a class of metabolites produced through fungal fermentation — are considered the main active ingredients. Monacolins, particularly monacolin K, work in the same way as statin medications, which involves the inhibition of a key enzyme involved in cholesterol synthesis, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase.[4] Therefore, RYR effectively reduces the body's own synthesis of cholesterol. Interestingly, the pigments found in RYR may also contribute to this lipid-lowering effect. Animal research suggests that these pigments may influence lipid metabolism and lead to an increase in the excretion of cholesterol, triglycerides, and bile acids in the feces.[22]

What are other names for Red Yeast Rice?
Note that Red Yeast Rice is also known as:
  • RYR
  • Hongqu
  • Red koji
  • Angkak
  • Monascus
  • Red fermented rice
  • Red mold rice
  • Xueshikang (a Traditional Chinese Medicine standardized extract)
  • Zhibituo (a Traditional Chinese Medicine standardized extract)
Red Yeast Rice should not be confused with:
  • Lovastatin (active ingredient)
  • Monascus purpureus (mold used in processing)
Dosage information

In clinical trials, the most common dosage of RYR is 600 mg twice daily. This dose has demonstrated effectiveness for reducing LDL cholesterol, improving atherosclerosis, and lowering the risk of major adverse cardiac events.[3][4][5] Importantly, most clinical trials have used a traditional Chinese medicine standardized extract, Xuezhikang. At a dose of 600 mg twice daily, Xuexhikang would provide about 10 mg daily of the active compound monacolin K, which is suggested to be the adequate amount for reducing LDL cholesterol.[6][7] Ultimately, most supplements don’t disclose the amount of monacolin K they contain, which makes it challenging to ensure adequate doses are achieved.

Supplements Demystified: Get Our Unbiased, Evidence-Based Guide

Examine Database: Red Yeast Rice
What works and what doesn't?

Unlock the full potential of Examine

Get started

Don't miss out on the latest research

Update History
  1. ^Red Yeast Rice: What You Need To KnowNIH.(2022 Nov)
  2. ^Defined Organism Substance - MonascusHealth Canada.(2023 Mar)
  3. ^Wang S, Chen Y, Wang R, Ma B, Wang Z, Tang G, Wang S, He Y, Qu LEffectiveness of red yeast rice on carotid atherosclerosis: A systematic review and meta-analysis.Front Pharmacol.(2022)
  4. ^Sungthong B, Yoothaekool C, Promphamorn S, Phimarn WEfficacy of red yeast rice extract on myocardial infarction patients with borderline hypercholesterolemia: A meta-analysis of randomized controlled trials.Sci Rep.(2020-Feb-17)
  5. ^Li P, Wang Q, Chen K, Zou S, Shu S, Lu C, Wang S, Jiang Y, Fan C, Luo YRed Yeast Rice for Hyperlipidemia: A Meta-Analysis of 15 High-Quality Randomized Controlled Trials.Front Pharmacol.(2021)
  6. ^Xiong X, Wang P, Li X, Zhang Y, Li SThe effects of red yeast rice dietary supplement on blood pressure, lipid profile, and C-reactive protein in hypertension: A systematic review.Crit Rev Food Sci Nutr.(2017-Jun-13)
  7. ^Zhu B, Qi F, Wu J, Yin G, Hua J, Zhang Q, Qin LRed Yeast Rice: A Systematic Review of the Traditional Uses, Chemistry, Pharmacology, and Quality Control of an Important Chinese Folk Medicine.Front Pharmacol.(2019)
  8. ^Buzzelli L, Segreti A, Di Gioia D, Lemme E, Squeo MR, Nenna A, Di Gioia GAlternative lipid lowering strategies: State-of-the-art review of red yeast rice.Fitoterapia.(2023-Nov-04)
  9. ^Fogacci F, Banach M, Mikhailidis DP, Bruckert E, Toth PP, Watts GF, Reiner Ž, Mancini J, Rizzo M, Mitchenko O, Pella D, Fras Z, Sahebkar A, Vrablik M, Cicero AFG, ,Safety of red yeast rice supplementation: A systematic review and meta-analysis of randomized controlled trials.Pharmacol Res.(2019-May)
  10. ^Rahmani P, Melekoglu E, Tavakoli S, Malekpour Alamdari N, Rohani P, Sohouli MHImpact of red yeast rice supplementation on lipid profile: a systematic review and meta-analysis of randomized-controlled trials.Expert Rev Clin Pharmacol.(2023-Jan)
  11. ^Arrigo F G Cicero, Federica Fogacci, Alberto ZambonRed Yeast Rice for Hypercholesterolemia: JACC Focus SeminarJ Am Coll Cardiol.(2021 Feb 9)
  12. ^Yuan R, Yuan Y, Wang L, Xin Q, Wang Y, Shi W, Miao Y, Leng SX, Chen K, Cong W,Red Yeast Rice Preparations Reduce Mortality, Major Cardiovascular Adverse Events, and Risk Factors for Metabolic Syndrome: A Systematic Review and Meta-analysis.Front Pharmacol.(2022)
  13. ^Li JJ, Hu SS, Fang CH, Hui RT, Miao LF, Yang YJ, Gao RLEffects of xuezhikang, an extract of cholestin, on lipid profile and C-reactive protein: a short-term time course study in patients with stable angina.Clin Chim Acta.(2005-Feb)
  14. ^Zhao SP, Liu L, Cheng YC, Shishehbor MH, Liu MH, Peng DQ, Li YLXuezhikang, an extract of cholestin, protects endothelial function through antiinflammatory and lipid-lowering mechanisms in patients with coronary heart disease.Circulation.(2004-Aug-24)
  15. ^Liu L, Zhao SP, Cheng YC, Li YLXuezhikang decreases serum lipoprotein(a) and C-reactive protein concentrations in patients with coronary heart disease.Clin Chem.(2003-Aug)
  16. ^Gerards MC, Terlou RJ, Yu H, Koks CH, Gerdes VETraditional Chinese lipid-lowering agent red yeast rice results in significant LDL reduction but safety is uncertain - a systematic review and meta-analysis.Atherosclerosis.(2015-Jun)
  17. ^Banach M, Norata GDRhabdomyolysis or Severe Acute Hepatitis Associated with the Use of Red Yeast Rice Extracts: an Update from the Adverse Event Reporting Systems.Curr Atheroscler Rep.(2023-Nov)
  18. ^Bhavin B Adhyaru, Terry A JacobsonSafety and efficacy of statin therapyNat Rev Cardiol.(2018 Dec)
  19. ^Mendes P, Robles PG, Mathur SStatin-induced rhabdomyolysis: a comprehensive review of case reports.Physiother Can.(2014)
  20. ^Perdices EV, Medina-Cáliz I, Hernando S, Ortega A, Martín-Ocaña F, Navarro JM, Peláez G, Castiella A, Hallal H, Romero-Gómez M, González-Jiménez A, Robles-Díaz M, Lucena MI, Andrade RJHepatotoxicity associated with statin use: analysis of the cases included in the Spanish Hepatotoxicity Registry.Rev Esp Enferm Dig.(2014-Apr)
  21. ^Cohen PA, Avula B, Khan IAVariability in strength of red yeast rice supplements purchased from mainstream retailers.Eur J Prev Cardiol.(2017-Sep)
  22. ^Zhou W, Guo R, Guo W, Hong J, Li L, Ni L, Sun J, Liu B, Rao P, Lv XMonascus yellow, red and orange pigments from red yeast rice ameliorate lipid metabolic disorders and gut microbiota dysbiosis in Wistar rats fed on a high-fat diet.Food Funct.(2019-Feb-20)
  23. ^Bin Wu, Jie-Feng Huang, Bang-Jian He, Chen-Wei Huang, Jian-Hua LuPromotion of Bone Formation by Red Yeast Rice in Experimental Animals: A Systematic Review and Meta-AnalysisBiomed Res Int.(2020 Aug 8)
  24. ^An T, Hao J, Sun S, Li R, Yang M, Cheng G, Zou MEfficacy of statins for osteoporosis: a systematic review and meta-analysis.Osteoporos Int.(2017-Jan)
  25. ^Chou R, Cantor A, Dana T, Wagner J, Ahmed AY, Fu R, Ferencik MStatin Use for the Primary Prevention of Cardiovascular Disease in Adults: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force.JAMA.(2022-Aug-23)
  26. ^Mills EJ, Wu P, Chong G, Ghement I, Singh S, Akl EA, Eyawo O, Guyatt G, Berwanger O, Briel MEfficacy and safety of statin treatment for cardiovascular disease: a network meta-analysis of 170,255 patients from 76 randomized trials.QJM.(2011-Feb)
  27. ^Fukami H, Higa Y, Hisano T, Asano K, Hirata T, Nishibe SA Review of Red Yeast Rice, a Traditional Fermented Food in Japan and East Asia: Its Characteristic Ingredients and Application in the Maintenance and Improvement of Health in Lipid Metabolism and the Circulatory System.Molecules.(2021-Mar-15)
Examine Database References
  1. Low-density lipoprotein (LDL) - Li P, Wang Q, Chen K, Zou S, Shu S, Lu C, Wang S, Jiang Y, Fan C, Luo YRed Yeast Rice for Hyperlipidemia: A Meta-Analysis of 15 High-Quality Randomized Controlled Trials.Front Pharmacol.(2021)
  2. Low-density lipoprotein (LDL) - Li M, He Q, Chen Y, Li B, Feng B, Zhang Z, Wang JXuezhikang Capsule for Type 2 Diabetes with Hyperlipemia: A Systematic Review and Meta-Analysis of Randomized Clinical Trails.Evid Based Complement Alternat Med.(2015)
  3. Heart Attack Risk - Sungthong B, Yoothaekool C, Promphamorn S, Phimarn WEfficacy of red yeast rice extract on myocardial infarction patients with borderline hypercholesterolemia: A meta-analysis of randomized controlled trials.Sci Rep.(2020-Feb-17)
  4. Atherosclerotic Signs - Wang S, Chen Y, Wang R, Ma B, Wang Z, Tang G, Wang S, He Y, Qu LEffectiveness of red yeast rice on carotid atherosclerosis: A systematic review and meta-analysis.Front Pharmacol.(2022)