Active constituents: In addition to rice starch, protein, fiber, sterols, and fatty acids, red yeast rice contains numerous
active constituents, including monacolin K, dihydromonacolin, and monacolin I to VI.
Researchers have determined that one of the ingredients in red yeast rice, called monacolin
K, inhibits the production of cholesterol by
stopping the action of a key enzyme in the liver (e.g., HMG-CoA reductase) that is responsible
for manufacturing cholesterol.6 The drug
lovastatin (Mevacor®) acts in a similar fashion to this red yeast rice ingredient.
However, the amount per volume of monacolin K in red yeast rice is small (0.2% per 5 mg) when
compared to the 20–40 mg of lovastatin available as a prescription drug.7
This has prompted researchers to suggest that red yeast rice may have other ingredients, such
as sterols, that might also contribute to lowering cholesterol.
Along with its evaluation in animal trials,8 red yeast rice has been clinically
investigated as a therapy for reducing
cholesterol in two human trials. In one trial, both men and women taking 1.2 grams
(approximately 13.5 mg total monacolins) of a concentrated red yeast rice extract per day for
two months had significant decreases in serum cholesterol levels.9 In addition,
people taking red yeast rice had a significant increase in HDL (“good”)
cholesterol and a decrease in LDL (“bad”) cholesterol. Elevated triglycerides were also found to be lowered.
A double-blind trial at the UCLA School of Medicine determined that red yeast rice in the
amount of 2.4 grams per day (approximately 10 mg total monacolins) in capsules significantly
decreased total- and LDL-cholesterol levels in a sample of people with elevated cholesterol
after 12 weeks of therapy. Triglycerides were also reduced in those taking red yeast rice.
However, unlike the original study, HDL values did not increase
substantially.10
How much is usually taken? The red yeast rice used in various
studies was a proprietary product called Cholestin®, which contains ten different
monacolins. The amount of Cholestin used in these studies was 1.2–2.4 grams (5–10
mg of monacolins) per day in divided amounts for 8-12 weeks.11 12
Note: Cholestin has been banned in the United States, as a result of a lawsuit
alleging patent infringement.
Other red yeast rice products currently on the market differ from Cholestin in their
chemical makeup. None contain the full complement of ten monacolin compounds that are present
in Cholestin, and some contain a potentially toxic fermentation product called
citrinin.13 Until further information is available, red yeast rice products other
than Cholestin cannot be recommended
References:
1. Burnham TH, Sjweain SL, Short RM (eds). Monascus. In: The Review
of Natural Products. St. Louis, MO: Facts and Comparisons, 1997.
2. Burnham TH, Sjweain SL, Short RM (eds). Monascus. In: The Review
of Natural Products. St. Louis, MO: Facts and Comparisons, 1997.
3. Hsu Hong-Yen. Oriental Materia Medica. Long Beach, CA:
Oriental Healing Arts Institute, 1986, 731–2.
4. Burnham TH, Sjweain SL, Short RM (eds). Monascus. In: The Review
of Natural Products. St. Louis, MO: Facts and Comparisons, 1997.
5. Hsu Hong-Yen. Oriental Materia Medica. Long Beach, CA:
Oriental Healing Arts Institute, 1986, 731–2.
6. Heber D, Yip I, Ashley JM, et al. Cholesterol-lowering effects of a
proprietary Chinese red-yeast-rice dietary supplement. Am J Clin Nutr
1999;69:231–6.
7. Heber D, Yip I, Ashley JM, et al. Cholesterol-lowering effects of a
proprietary Chinese red-yeast-rice dietary supplement. Am J Clin Nutr
1999;69:231–6.
8. Li C, Zhu Y, Wang Y, et al. Monascus purpureus-fermented rice
(red yeast rice): a natural food product that lowers blood cholesterol in animal models of
hypercholesterolemia. Nutr Res 1998;18:71–81.
9. Wang J, Lu Z, Chi J, et al. Multicenter clinical trial of the serum
lipid-lowering effects of a Monascus purpureus (red yeast) rice preparation from
traditional Chinese medicine. Curr Ther Res 1997;58:964–77.
10. Heber D, Yip I, Ashley JM, et al. Cholesterol-lowering effects of a
proprietary Chinese red-yeast-rice dietary supplement. Am J Clin Nutr
1999;69:231–6.
11. Heber D, Yip I, Ashley JM, et al. Cholesterol-lowering effects of a
proprietary Chinese red-yeast-rice dietary supplement. Am J Clin Nutr
1999;69:231–6.
12. Wang J, Lu Z, Chi J, et al. Multicenter clinical trial of the serum
lipid-lowering effects of a Monascus purpureus (red yeast) rice preparation from
traditional Chinese medicine. Curr Ther Res 1997;58:964–77.
13. 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. J Altern Complement Med 2001;7:133-9.
14. Wang J, Lu Z, Chi J, et al. Multicenter clinical trial of the serum
lipid-lowering effects of a Monascus purpureus (red yeast) rice preparation from
traditional Chinese medicine. Curr Ther Res 1997;58:964–77.
15. Burnham TH, Sjweain SL, Short RM (eds). Monascus. In: The Review
of Natural Products. St. Louis, MO: Facts and Comparisons, 1997.
Copyright © 2002 Healthnotes, Inc. All rights reserved.
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purposes only. It is based on scientific studies (human, animal, or in vitro),
clinical experience, or traditional usage as cited in each article. The results reported may
not necessarily occur in all individuals. For many of the conditions discussed, treatment with
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before making any changes in prescribed medications. Information expires December 2003.