Red yeast rice is a popular supplement among practitioners of Traditional Chinese Medicine and functional medicine, but red yeast rice products have only sat on Western shelves for a few decades.
It contains a compound called monacolin K that works similarly to the cholesterol-reducing drugs called statins. Because of this similarity, some dietary supplements that claim to reduce your blood fat levels contain extracts of red yeast rice.
However, there are safety concerns around red yeast rice supplements.
Some people use supplements to balance their health needs, and they can be helpful for people who don’t get enough of a specific nutrient.
At ZOE, we run the largest nutrition study in the world, and we look at how your body responds to a range of different foods and food combinations.
Our at-home test and program can help you build a balanced, nutritious diet in the best way for your unique dietary needs. The test shows how your blood sugar and fat levels respond to different foods.
These responses are important because they are linked to your risk of lifelong conditions like type 2 diabetes and heart disease.
Through our test, you can also find out which bacteria live in your gut microbiome. ZOE then puts this data to work, making food recommendations built around what works for your body.
And read on to learn more about red yeast rice.
What is red yeast rice?
Manufacturers produce red yeast rice by fermenting rice with a yeast called Monascus purpureus. Aside from its role in Traditional Chinese Medicine, it’s also used as an ingredient in some Chinese dishes like Peking duck.
While its medical roots are ancient, red yeast rice has made its way into Western drug stores as an over-the-counter supplement.
Supplements provide a much higher dose of active chemicals than the food, and many red yeast rice products claim to reduce cholesterol.
However, as with many supplements, that’s not quite the whole picture.
The supposed benefits of red yeast rice
People in East Asian countries that practice Traditional Chinese Medicine have used red yeast rice for thousands of years to help people manage health problems, such as:
slow blood circulation
As a food, red yeast rice can form part of a healthy diet. But the manufacturers of red yeast rice supplements claim that they can reduce blood cholesterol levels.
Can red yeast rice really reduce cholesterol?
Some red yeast rice products can theoretically help you balance cholesterol levels.
Cholesterol is essential for your body to function. But elevated cholesterol levels, if left untreated, can contribute to a higher risk of heart disease over time.
Most of the cholesterol in your body is produced by the liver. Statins slow down how much cholesterol your liver produces.
The monacolin K in red yeast rice is chemically identical to the active ingredient in a pharmaceutical statin called lovastatin.
Some yeast strains produce enough monacolin K to lower cholesterol.
However, the United States Food and Drug Administration (FDA) have banned these products because levels of the active component are so high that they are classed as “unapproved new drugs.”
Because of this, red yeast rice products now provide far less monacolin K and may have far less impact on cholesterol levels.
Also, red yeast rice supplement packaging does not make the dosage of monacolin K clear. Manufacturers provide the amount of red yeast rice in the formula rather than the amount of monacolin K.
Is red yeast rice safe?
There are genuine safety concerns about some red yeast rice products. Because monacolin K acts as a natural statin, some supplements work more like medications. However, the FDA regulate supplements and medications in different ways.
The FDA have banned red yeast rice products that contain more than tiny amounts of monacolin K, and this means they might not reduce your cholesterol as much as they promise.
The fermentation process for making red yeast rice can also introduce a poisonous byproduct called citrinin. Citrinin is a mycotoxin — a toxic substance that can develop while fermenting rice in Monascus.
If you are worried about your blood cholesterol levels, it’s better to speak with your doctor rather than take a supplement with unknown levels of active ingredients.
Possible side effects of red yeast rice supplements
Taking red yeast rice supplements can cause the same side effects as statins.
In one case, doctors admitted an otherwise healthy, active 64-year-old woman to the hospital after she took a 1.2-gram red yeast supplement for 6 weeks. The supplement led to liver poisoning.
The woman recovered following steroid treatment, but this is not the only recorded hospital admission linking red yeast rice supplements and liver poisoning.
Large doses of monacolin K also increase the risk of rhabdomyolysis — a condition where your muscles break down. Compounds from the damaged muscles then enter the bloodstream, where they can damage your kidneys.
Red yeast rice supplements can interact with the same medications as statins; these include:
other drugs that reduce cholesterol, including gemfibrozil
cyclosporine, a drug used to treat psoriasis and rheumatoid arthritis
colchicine, a medicine to manage inflammation
ranolazine, a chest pain medication
If you’re thinking about taking red yeast rice supplements, ask your doctor about these interactions and whether your specific medications will cause health problems.
It’s also important not to swap prescribed medications for supplements, as this could have unexpected harmful effects.
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How do red yeast rice products vary?
Depending on which strain of yeast the manufacturers use during fermentation, the makeup of each red yeast rice product may be different.
This means that one product could contain high concentrations of monacolin K, while another with an identical ingredients list could provide barely any. Red yeast rice supplement producers only list the amount of red yeast rice instead of the dosage of monacolin K.
Due to the fermentation process, harmful substances can also end up in some red yeast rice supplements. These include the mycotoxin citrinin.
Is red yeast rice legal?
Red yeast rice products aren’t illegal, but there is a maximum dosage of monacolin K they can have before the FDA class them as drugs.
The FDA don't regulate nutritional supplements in the same way as drugs. However, if a red yeast rice supplement has high levels of monacolin K, the FDA consider it an unapproved drug.
In 2019, the FDA took action against two supplement makers over three red yeast rice supplements with high levels of monacolin K.
While red yeast rice isn’t illegal, it comes with heavy cautions and shouldn’t feature in your daily healthcare plan without advice from a healthcare professional.
Alternatives to red yeast rice for reducing cholesterol
There are safe, natural, and enjoyable ways to keep your blood cholesterol balanced. You don’t need to take a risky supplement with an ingredient list that’s hiding something.
Other ways to reduce cholesterol include:
Staying physically active. The American Heart Association recommend getting 150 minutes of moderate-to-vigorous-intensity exercise every week. That’s just a target — you can work up to it slowly, finding ways to be active that are comfortable and sustainable within your lifestyle.
Avoiding smoking, or quitting if you already do. Smoking increases levels of “bad” cholesterol in the blood. However, quitting smoking increases levels of “good” cholesterol and reduces “bad” cholesterol.
Maintaining a moderate body weight. If your body mass index (BMI) is 25 or over, losing 5–10% of your body weight could significantly affect your cholesterol levels. Work with a healthcare professional to identify your moderate weight range.
One of the most powerful tools for controlling blood fats is a diet that your body responds to in a healthy way.
The ZOE at-home test can identify how your blood fats respond to different foods. Using that information, we recommend a diet that’s right for your body. We also measure your blood sugar response and check the health of your gut microbiome.
If you have familial hypercholesterolemia, these lifestyle changes can all be incredibly beneficial. However, you will likely still need to take prescribed medications to help control your cholesterol levels.
Red yeast rice supplements claim to reduce cholesterol, and some do. But they can have significant side effects and don’t come with the same FDA oversight as medications.
It’s better for your overall health to avoid these supplements and manage cholesterol levels through regular exercise and diet. In some cases, your doctor may also suggest that you take medication.
The ZOE at-home test can track your personal responses to food and the makeup of your gut microbiome. The ZOE program helps you pick the best foods for your body, so you can reach your personal health goals.
FDA warns consumers to avoid red yeast rice products promoted on Internet as treatments for high cholesterol. (2007). https://www.in.gov/health/food-protection/recalls-and-advisories/2007-advisories/red-yeast-rice-products/
Lovastatin tablet. (2021). https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=df7ddf4f-d569-431e-81f1-9129d7043150
Prevention and treatment of high cholesterol (hyperlipidemia). (2020). https://www.heart.org/en/health-topics/cholesterol/prevention-and-treatment-of-high-cholesterol-hyperlipidemia
Red yeast rice. (n.d.). https://www.nccih.nih.gov/health/red-yeast-rice
Red yeast rice supplement “has the potential to cause” liver damage, doctors warn. BMJ. (2019). https://www.bmj.com/company/newsroom/red-yeast-rice-supplement-has-the-potential-to-cause-liver-damage-doctors-warn/
Red yeast rice: A systematic review of the traditional uses, Chemistry, pharmacology, and quality control of an important Chinese folk medicine. Frontiers In Pharmacology. (2019). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6901015/