Red yeast rice may be appealing because it's "natural," but you need to be careful. Experts have not studied it extensively. The ideal dosing and long-term safety are unclear. It could be dangerous for some people. And because the ingredients of different brands of red yeast rice extract might vary so much, it's hard to make firm statements about its effectiveness or safety.
What Is Red Yeast Rice?
Red yeast rice is a substance that's extracted from rice that's been fermented with a type of yeast called Monascus purpureus. It's been used in China and other Asian countries for centuries as a traditional medicine. It's also used as a food coloring, additive, and preservative.
Red yeast rice naturally contains several ingredients that may help control cholesterol levels. These include a number of monacolins, most importantly monacolin K. It also contains sterols, isoflavones, and monounsaturated fatty acids, or "healthy fats."
Is Red Yeast Rice a Drug or a Supplement?
So on one hand, red yeast rice is a traditional remedy that helps lower cholesterol. On the other, the pharmaceutical manufacturer of Mevacor argues that it owns the rights to the ingredient lovastatin.
This confusion extends to how the supplement is sold in the U.S. Because red yeast rice contains a substance classified as a prescription drug, the FDA has attempted to control its sale. In 2007, the FDA asked that three red yeast rice products -- Cholestrix by Sunburst Organics and two red yeast rice formulations by Swanson Healthcare Products (Red Yeast Rice and Red Yeast Rice/Policosonal Complex) -- be withdrawn from the market because they contained lovastatin. The FDA cited a risk of severe muscle problems that could lead to kidney disease.
Despite the FDA's attempts, many people in the U.S. still manage to get similar red yeast rice extracts from other countries or the Internet.
How Well Does Red Yeast Rice Lower Cholesterol?
Studies have shown that red yeast rice can significantly lower levels of total cholesterol and specifically LDL, or "bad" cholesterol. One showed that taking 2.4 grams per day of red yeast rice reduced LDL levels by 22% and total cholesterol by 16% in 12 weeks. Another study showed that taking 1.2 grams per day lowered LDL levels by 26% in just eight weeks.
However, the studies of red yeast rice have so far been fairly small and didn't last long enough to reveal the long-term effects.
What Is the Correct Dosage of Red Yeast Rice?
Since research into red yeast rice is still in its early stages, experts still aren't sure of what the ideal dose should be. The amounts taken in some studies have varied from 1.2 to 2.4 grams per day. In China and other countries, estimates of average daily consumption are much higher.
Keep in mind that amount of monacolin -- perhaps the most important ingredient -- in a red yeast rice extract can vary a lot. There are many different strains of the yeast. Different types of fermentation are used. One study of different brands of red yeast rice supplements showed that the amount of monacolin ranged from 0% to 0.58%.
So even though studies have shown that red yeast rice can lower cholesterol, you can't really know if the supplement brand you're using will have that effect.
What Are the Risks of Red Yeast Rice?
Studies have shown that red yeast rice side effects are mild, like headaches, heartburn, and upset stomach. Side effects from prescription lovastatin include elevation of liver enzymes and muscle enzymes, muscle problems, and liver problems.
But more research needs to be done before we can know about the long-term safety of red yeast rice. We do know that some types of red yeast rice may be more dangerous than others because of high levels of other substances such as citrinic acid.
Red yeast rice also shares some of the same risks as statins, the class of drugs containing lovastain. Experts say that the risks of lovastatin would logically apply to red yeast rice -- elevation of liver and muscle enzymes, muscle problems, and liver problems.
Red yeast rice may not be safe for everyone. You should not take it if you:
In addition, anyone taking one of the following medicines should not use red yeast rice:
- Statins to control cholesterol such as rosuvastatin (Crestor), fluvastatin (Lescol), atorvastatin (Lipitor), pravastatin (Pravachol), and simvastatin (Zocor)
- Other cholesterol drugs such as gemfibrozil (Lopid) and fenofibrate (TriCor)
- Drugs to suppress the immune system, like cyclosporine
- Antifungal drugs such as fluconazole (Diflucan), ketoconazole (Nizoral), and itraconazole (Sporanox)
- The antibiotics erythromycin and clarithromycin (Biaxin)
- Serzone, an antidepressant
- Protease inhibitors, used to treat HIV
People who have allergies to fungus or yeast should also be wary of using red yeast rice.
Whatever the state of your health, always talk to your doctor before you start using red yeast rice or any other supplement. Remember that all brands are not equal, and that red yeast rice isn't safe for everyone. Though red yeast rice looks like a promising treatment, more research needs to be done. For now, you should be cautious.