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Red rice

Red rice, also called red fermented rice, red mold rice or red yeast rice, is a traditional Chinese culinary and medicinal product. Supplements containing red rice are marketed to lower cholesterol and related lipid levels. Red rice products may not be safe and harmless. Some may have the same side effects as certain cholesterol-lowering drugs and some may contain certain potentially harmful contaminants.

Red mold rice is produced by fermenting rice with Monascus strains. Red rice has also been used as a food additive in China for centuries (e.g. in Peking duck, pork and red rice wine). It lowers cholesterol by 35%. A comparison of red rice with a medicinal cholesterol-lowering drug - pravastatin - showed a better effect of red rice. A cholesterol value of 280 mg/dl with pravastatin fell to 228 mg/dl after 8 weeks, while treatment with red rice reduced it to 220 mg/dl in the same time without any side effects.

The red mold rice produced in this way is bacteriostatic, which is why its powder or extract is used as a preservative. Due to its red pigments, red fermented rice is used for food coloring and also to improve taste. Red rice powder has a physiological effect due to the lipid-lowering substances known as monacolins, which are formed during the fermentation process with Monascus strains. Monacolins inhibit the cholesterol production of the liver in a dose-dependent manner, thus lowering the cholesterol level and influencing the lipid level of the blood.

Key facts

Some red mold rice products contain substantial amounts of monacolin K, which is chemically identical to the active ingredient in the cholesterol-lowering drug lovastatin. These products can lower blood cholesterol levels and have the same side effects and interactions as lovastatin. Other red rice products contain little or no monacolin K. It is not known whether these products have an effect on blood cholesterol levels. Consumers have no way of knowing how much monacolin K is present in most red rice products. The label of these products usually only states the amount of red rice they contain and not the amount of monacolin K. In some countries, red rice products that contain more than trace amounts of monacolin K are considered drugs and may not be sold as supplements. Some products contain contamination with citrinin, which can lead to kidney failure.

About red rice

Red fermented rice is produced by cultivating rice with different strains of Monascus Purpureus yeast. Some red rice preparations are used in Chinese cuisine, including Peking duck. Others are marketed as nutritional supplements to lower cholesterol and related lipid levels. Some products contain substances called monacolins, which are produced by yeast. Monacolin K is chemically identical to the active ingredient in the cholesterol-lowering drug lovastatin, which belongs to the category of drugs known as statins. These drugs lower blood cholesterol levels by reducing the production of cholesterol in the liver.

The composition of red yeast rice products varies depending on the yeast strains and the cultivation conditions used to produce them. The strains and conditions used to produce culinary red rice are different from those used in the manufacture of products intended to lower cholesterol levels. Research conducted by the U.S. Food and Drug Administration indicates that red rice sold as a food product contains only trace amounts of monacolin K or no monacolin K at all. In 2008 and 2009, sales of red rice products amounted to approximately 20 million dollars per year.

Safety

The same types of side effects that can occur in patients taking lovastatin as a medication can also occur in people taking red rice products containing monacolin K. Potential side effects include myopathy (muscle symptoms such as pain and weakness), rhabdomyolysis (a condition in which muscle fibers break down and substances are released into the bloodstream that can damage the kidneys), and liver toxicity. Each of these three side effects has been observed in people using red rice products. Red rice supplements should not be used by pregnant or breastfeeding women.

Lovastatin may interact with a number of medications, increasing the risk of rhabdomyolysis. These medications include cholesterol-lowering agents, certain antibiotics, the antidepressant nefazodone, medications used to treat fungal infections, and medications used to treat HIV infection. Red rice, which contains monacolin K, could interact with medications in the same way.

If the process of making red rice is not carefully controlled, a substance called citrinin can form. Citrinin has been shown to cause kidney failure in laboratory animals and genetic defects in human cells. A 2011 analysis of red rice products sold as nutritional supplements found that 4 out of 11 products tested contained such a contaminant.

What the science says

Red rice products containing substantial amounts of monacolin K may lower blood cholesterol levels. No results have yet been published from studies using red rice containing little or no monacolin K, so it is not known whether these products have an effect on cholesterol levels.

Results of clinical trials

In human clinical trials with red rice products containing substantial amounts of monacolin K, these products lowered blood levels of total cholesterol and harmful LDL cholesterol, which is associated with cardiovascular disease. It is important to emphasize that all of these clinical studies used products that contained substantial amounts of monacolin K.

An analysis conducted in 2011 showed that some of the red rice products available on the market contained very little monacolin K. These products may have little or no effect on blood cholesterol levels. For this reason, even if the participants in the clinical trials were able to lower their cholesterol levels by taking red rice, they will not necessarily be able to achieve the same results.

In one of the clinical trials, the product tested produced a stronger cholesterol-lowering effect than would have been expected based on its monacolin K content. Further studies suggest that other monacolins or other substances contained in this product may have contributed to its cholesterol-lowering effect.

Tolerance of red rice products

Two studies suggest that some people who cannot tolerate statin drugs due to side effects (muscle pain and/or weakness) were able to tolerate red rice. It is unknown whether the lower amount of monacolin K present in red rice products compared to the amount of active ingredients in medications contributed to this better tolerance or whether other factors were responsible.

Precautions and warnings

One should not use red rice to replace conventional therapy or attempt to lower high cholesterol levels without medical assistance. Pregnant or breastfeeding women or women trying to become pregnant should not use red rice in supplement form. If you want to give red rice products to children, you should consult a doctor beforehand. Red rice products should not be used in addition to prescription statin drugs.

References

  1. Barnes PM, Bloom B, Nahin RL. Complementary and alternative medicine use among adults and children: United States, 2007.CDC National Health Statistics Report #12. 2008.
  2. Becker DJ, Gordon RY, Halbert SC, et al. Red yeast rice for dyslipidemia in statin-intolerant patients. A randomized trial.Annals of Internal Medicine. 2009;150(12):830-839.
  3. Gordon RY, Becker DJ. The role of red yeast rice for the physician.Current Atherosclerosis Reports. 2011;13(1):73-80.
  4. Gordon RY, Cooperman T, Obermeyer W, et al. Marked variability of monacolin levels in commercial red yeast rice products: buyer beware!Archives of Internal Medicine. 2010;170(19):1722-1727.
  5. Halbert SC, French B, Gordon RY, et al. Tolerability of red yeast rice (2,400 mg twice daily) versus pravastatin (20 mg twice daily) in patients with previous statin intolerance.American Journal of Cardiology. 2010;105:198-204.
  6. Heber D, Lembertas A, Lu QY, et al. An analysis of nine proprietary Chinese red yeast rice dietary supplements: implications of variability in chemical profile and contents.Journal of Alternative and Complementary Medicine. 2001;7(2):133-139.
  7. Klimek M, Wang S, Ogunkanmi A. Safety and efficacy of red yeast rice (Monascus purpureus) as an alternative therapy for hyperlipidemia.P&T: A Peer-Reviewed Journal for Formulary Management. 2009;34(6):313-327.
  8. Li Z, Seeram NP, Lee R, et al. Plasma clearance of lovastatin versus Chinese red yeast rice in healthy volunteers.Journal of Alternative and Complementary Medicine. 2005;11(6):1031-1038.
  9. U.S. Food and Drug Administration.FDA Warns Consumers to Avoid Red Yeast Rice Products Promoted on Internet as Treatments for High Cholesterol: Products Found to Contain Unauthorized Drug. U.S. Food and Drug Administration Web site. Accessed at www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/2007/ucm108962.htm on March 8, 2012.