Red yeast rice, also called Went Yeast, has been used for centuries in China as both food and medicine. It is made by fermenting a type of yeast called Monascus purpureus over red rice. In Chinese medicine, red yeast rice is used to lower cholesterol, improve blood circulation, and improve digestion.
Red yeast rice contains chemicals that are similar to prescription statin medications. One of these, called monacolin K, has the same makeup as the drug lovastatin (Mevacor). Doctors prescribe statins to lower LDL (“bad”) cholesterol levels and help reduce the risk of heart disease.
Researchers are not sure if red yeast rice lowers cholesterol because of the statin-like chemical or because of other things in red yeast rice, such as unsaturated fatty acids, isoflavones, and phytosterols. But because many red yeast rice supplements did have monacolin, the Food and Drug Administration (FDA) considered them to be drugs. Manufacturers were supposed to remove any red yeast rice products with monacolin from the market. As a result, many of the red yeast rice products you can buy may not contain monacolin. Unfortunately, there is no way to tell whether a product contains moacolin because it is not listed on the label.
Red Yeast Rice Side Effects
Side effects of red yeast rice are rare but can include:
- Headache
- Stomachache or bloating
- Gas
- Dizziness
- Heartburn
- Muscle aches and weakness. This can lead to a rare but serious condition called rhabdomyolysis. Stop taking red yeast rice immediately and call your doctor.
Pregnancy and Breastfeeding
Pregnant and breastfeeding women should not take red yeast rice.
Pediatric Use
People under 20 should not take red yeast rice until more research is done.
Geriatric Use
No studies have looked at the safety of red yeast rice in older adults. However, elderly people who took 1,200 mg per day of red yeast rice in an 8-week study had no major side effects.
Red yeast rice might contain monacolin K, the same ingredient that is in the prescription cholesterol-lowering drug lovastatin. Lovastatin’s side effects include liver damage and muscle disorders (myopathy).
Don’t take red yeast rice if you’re pregnant, trying to become pregnant, or breastfeeding.
An older study raised the concern that some red yeast rice products contain a contaminant called citrinin, which can cause kidney failure. However, a more recent study that analyzed 14 red yeast rice dietary supplements didn’t find citrinin in any of them.
Interactions
Possible interactions include:
Alcohol: Don’t drink alcohol if you are taking red yeast rice. The combination might increase the risk of liver damage.
Cyclosporine (Neoral, Sandimmune): Taking this immunosuppressive drug with red yeast rice might increase the risk of myopathy.
Cytochrome P450 3A4 (CYP3A4) inhibitors: Taking red yeast rice with drugs, such as erythromycin, that inhibit this enzyme might increase the risk of harmful red yeast rice side effects.
Grapefruit: Drinking grapefruit juice and taking red yeast rice might increase the risk of the supplement’s harmful side effects.
Gemfibrozil (Lopid): Taking this cholesterol drug with red yeast rice might increase the risk of myopathy.
Hepatotoxic drugs, herbs, and supplements: Red yeast rice might contain monacolin K, which can cause liver damage in some people. Taking red yeast rice with these types of drugs, herbs, and supplements could increase the risk of liver damage.
Niacin: Taking red yeast rice with high-dose niacin might increase the risk of myopathy.
St. John’s wort: Taking this supplement with red yeast rice might reduce the effectiveness of red yeast rice.
Statin: Taking red yeast rice with other statins might increase the risk of harmful side effects.
FAQ
Is it ok to take red yeast rice every day?
The review suggests that consuming 3–10 milligrams (mg) of monacolin K daily may have low associated risks. Additionally, it indicates that red yeast rice is a safe and effective way to manage mild to moderate hypercholesterolemia in people with no additional cardiovascular risk factors.
How long does it take for red yeast rice to lower cholesterol?
In particular, its effectiveness is directly related to the amount of monacolin K within the extract (up to 10 mg/day). Consuming monacolin K on a daily basis reduces low-density lipoprotein (LDL) cholesterol plasma levels between 15% and 25% within 6 to 8 weeks.
What supplements should not be taken with red yeast rice?
Avoid using red yeast rice together with other herbal/health supplements that can harm your liver, such as androstenedione, chaparral, comfrey, DHEA, germander, kava, niacin, pennyroyal oil, and others. Grapefruit may interact with red yeast rice and lead to unwanted side effects. Avoid the use of grapefruit products.
Is red yeast rice hard on kidneys?
An older study raised the concern that some red yeast rice products contain a contaminant called citrinin, which can cause kidney failure. However, a more recent study that analyzed 14 red yeast rice dietary supplements didn’t find citrinin in any of them.
Is red yeast rice good for fatty liver?
Red yeast rice ameliorates non-alcoholic fatty liver disease by inhibiting lipid synthesis and NF-κB/NLRP3 inflammasome-mediated hepatic inflammation in mice.
Is red yeast rice harmful to the liver?
Red yeast rice is bright reddish-purple fermented rice that is used as a dietary supplement, predominantly as a cholesterol-lowering agent. The reddish-purple color derives from the mold Monascus purpureus. Red yeast rice use has been associated with very rare instances of acute, clinically apparent liver injury.
