Red Yeast Rice
Red
yeast rice is a traditional Chinese culinary and medicinal product. In
the United States, dietary supplements containing red yeast rice have
been marketed to help lower blood levels of cholesterol and related
lipids. Red yeast rice products may not be safe; some may have the same
side effects as certain cholesterol-lowering drugs, and some may
contain a potentially harmful contaminant. This fact sheet provides
basic information about red yeast rice, summarizes scientific research
on effectiveness and safety, discusses the legal status of red yeast
rice, and suggests sources for additional information.
Key Facts
Some
red yeast rice products contain substantial amounts of monacolin K,
which is chemically identical to the active ingredient in the
cholesterol-lowering drug lovastatin. These products may lower blood
cholesterol levels and can cause the same types of side effects and
drug interactions as lovastatin.
Other red yeast rice products
contain little or no monacolin K. It is not known whether these
products have any effect on blood cholesterol levels.
Consumers
have no way of knowing how much monacolin K is present in most red
yeast rice products. The labels on these products usually state only
the amount of red yeast rice that they contain, not the amount of
monacolin K.
The U.S. Food and Drug Administration (FDA) has
determined that red yeast rice products that contain more than trace
amounts of monacolin K are unapproved new drugs and cannot be sold
legally as dietary supplements.
Some red yeast rice products contain a contaminant called citrinin,
which can cause kidney failure.
Tell
all your health care providers about any complementary health
approaches you use. Give them a full picture of what you do to manage
your health. This will help ensure coordinated and safe care.
About Red Yeast Rice
Red
yeast rice is made by culturing rice with various strains of the yeast
Monascus purpureus.
Some preparations of red yeast rice are used in food products in
Chinese cuisine, including Peking duck. Others have been sold as
dietary supplements to lower blood levels of cholesterol and
related lipids.
Some
red yeast rice products contain substances called monacolins, which are
produced by the yeast. Monacolin K is chemically identical to the
active ingredient in the cholesterol-lowering drug lovastatin, which is
one of the drugs in the category known as statins. These drugs lower
blood cholesterol levels by reducing the production of cholesterol by
the liver.
The
composition of red yeast rice products varies depending on the yeast
strains and culture conditions used to manufacture them. The strains
and conditions used to produce culinary red yeast rice differ from
those used to produce products that are intended to lower cholesterol.
Tests performed by the FDA indicate that the red yeast rice sold as a
food product contains only traces of monacolin K or none
at all.
In
both 2008 and 2009, the most recent years for which data are available,
sales of red yeast rice dietary supplements were approximately $20
million per year. According to the 2007 National Health Interview
Survey, which included a comprehensive survey of the use of
complementary health approaches by Americans, 2.1 percent of
respondents (an estimated 1.8 million Americans) had used complementary
health approaches for cholesterol in the past year.
Safety
The
same types of side effects that can occur in patients taking lovastatin
as a drug can also occur in patients who take red yeast rice products
that contain monacolin K. Potential side effects include myopathy
(muscle symptoms such as pain and weakness), rhabdomyolysis (a
condition in which muscle fibers break down, releasing substances into
the bloodstream that can harm the kidneys), and liver toxicity. Each of
these three side effects has been reported in people who were taking
red yeast rice.
Red yeast rice supplements should not be used while pregnant
or breastfeeding.
Lovastatin
can interact with a variety of drugs to increase the risk of
rhabdomyolysis; these drugs include other cholesterol-lowering agents,
certain antibiotics, the antidepressant nefazodone, drugs used to treat
fungal infections, and drugs used to treat HIV infection. Red yeast
rice containing monacolin K could interact with drugs in the
same way.
If the process of culturing red yeast rice is not
carefully controlled, a substance called citrinin can form. Citrinin
has been shown to cause kidney failure in experimental animals and
genetic damage in human cells. In a 2011 analysis of red yeast rice
products sold as dietary supplements, 4 of 11 products were found to
contain this contaminant.
What the Science Says
Red
yeast rice products that contain substantial amounts of monacolin K can
lower blood cholesterol levels. Researchers have not reported results
of any studies of red yeast rice products that contain little or no
monacolin K, so whether these products have any effect on blood
cholesterol is unknown.
Results
of Clinical Trials
In
clinical trials (studies in people) of red yeast rice products that
contained substantial amounts of monacolin K, the products lowered
blood levels of total cholesterol and low-density lipoprotein (LDL)
cholesterol (the so-called bad cholesterol that is linked to increased
heart disease risk). It is important to emphasize that all of these
clinical trials used products that contained substantial amounts of
monacolin K. A 2011 analysis showed that some of the red yeast rice
products on the market contain very little monacolin K. These products
may have little or no effect on blood cholesterol levels. Therefore,
even though the participants in the clinical trials were able to lower
their cholesterol levels by taking red yeast rice, you might not be
able to achieve the same results.
In
one of the clinical trials, the tested product produced a
cholesterol-lowering effect greater than would be expected based on its
monacolin K content. Further investigations, supported by the National
Center for Complementary and Integrative Health (NCCIH), suggested that
other monacolins or other substances present in the product may have
contributed to its cholesterol-lowering effect.
Tolerability
of Red Yeast Rice Products
Two
studies supported by NCCIH have indicated that some people who had been
unable to tolerate statin drugs because of side effects (muscle pain or
weakness) were able to tolerate red yeast rice. It is uncertain whether
the smaller amount of monacolin K in the red yeast rice products, as
compared with the amounts of active ingredients in the drugs, accounted
for the greater tolerability or whether other factors
were responsible.
Legal Status of Red Yeast Rice
In
1998, the FDA determined that a red yeast rice product that contained a
substantial amount of monacolin K was an unapproved new drug, not a
dietary
supplement.
On several occasions since then, the FDA has taken action against
companies selling red yeast rice products that contain more than trace
amounts of monacolin K, warning them that it is against the law to
market these products as dietary supplements.
Despite
the FDA actions, some red yeast rice products currently on the market
in the United States may contain monacolin K. (Some products tested as
recently as 2011 have been found to contain it in substantial amounts.)
Other products may contain little or none of this component. Consumers
have no way of knowing how much monacolin K is present in most red
yeast rice products, and therefore have no way of knowing whether a
particular product is safe, effective, or legal. The labels on these
products usually state only the amount of red yeast rice that they
contain, not the amounts of monacolin K or other monacolins.
If You Are Considering Red Yeast Rice
Do
not use red yeast rice to replace conventional care or to postpone
seeing your health care provider about a health problem.
Do not
use red yeast rice dietary supplements if you are pregnant, trying to
become pregnant, or nursing a child. If you are considering giving a
child a red yeast rice dietary supplement, it is especially important
to consult the child's health care provider.
Do not take red yeast rice in addition to prescription
statin drugs.
Many
Web sites, including sales sites, have information about red yeast
rice. Be cautious when you evaluate information from the Web; not all
of it is trustworthy. For more information, see the NCCIH fact sheet
Evaluating
Web-Based Health Resources.
Federal
regulations for dietary supplements are very different from—and less
strict than—those for drugs. For more information about dietary
supplements, see NCCIH's fact sheet
Using Dietary Supplements Wisely.
Tell
all your health care providers about any complementary health
approaches you use. Give them a full picture of what you do to manage
your health. This will help ensure coordinated and safe care.
Key References
- 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.
- 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.
- Gordon
RY, Becker DJ. The
role of red yeast rice for the physician. Current Atherosclerosis Reports. 2011;13(1):73–80.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.