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Lipid Lowering Effects of Red Yeast Rice
Extract
by Jim English
Elevated serum cholesterol levels (hypercholesterolemia)
are a recognized risk factor for developing Coronary Heart Disease
(CHD), the leading cause of death in the United States.(1) Standard
approaches for controlling hypercholesterolemia include dietary
modifications, lifestyle changes, drug therapy and dietary supplements.
While moderately effective, most of these approaches suffer from
serious drawbacks: patient compliance issues (diet and lifestyle
changes), safety (drug side effects) and cost (drugs).
A newly
available food-source supplement has recently been shown
effective at lowering total cholesterol levels, reducing LDL
and triglyceride levels, and increasing HDL levels. The supplement,
Red Yeast Rice extract, is an exciting new addition to the existing
armamentarium of natural supplements that have been shown to
safely
and effectively reduce moderately elevated cholesterol levels.
Cholesterol, a lipid (fatty) component of all cellular membranes,
is required to support cellular integrity and for the biosynthesis
of vital hormones. Cholesterol levels can be influenced by dietary
modification (i.e.. reducing one’s intake of saturated and
transfatty acids) but the majority of cholesterol (about 80%) isn't
derived by dietary sources but is synthesized by the liver. Biosynthesis
of cholesterol is controlled by the rate limiting enzyme, HMG-CoA
(3-hydroxy-3-methylglutaryl coenzyme A) reductase.
Normally, cholesterol levels are regulated by
the liver via a biochemical feedback loop. When cholesterol levels
are low, liver production of HMG-CoA reductase leads to increased
biosynthesis of cholesterol. Conversely, when cholesterol levels
are elevated, the liver reduces production of HMG-CoA reductase,
halting further production of cholesterol. The proper functioning
of this feedback mechanism is vital for the maintenance of healthy
cholesterol levels. Unfortunately modern dietary habits and lifestyle
contribute to the disruption of this system, leading to elevated
cholesterol levels and increased risks for developing CHD.
Controlling total blood cholesterol levels can be an important
step to lowering one’s risk for developing CHD. For most
people, modifications in lifestyle may be enough to normalize
cholesterol
levels. Such modifications can include dietary changes, moderate
exercise, and regular use of antioxidants and other nutrients.
For those individuals who don't respond to
these methods, or for
those with a genetic predisposition to hypercholesterolemia, standard
medical therapy will employ drugs to bring cholesterol under control.
Among the current pharmaceutical agents of choice for lowering
LDL cholesterol levels are the bile acid sequestrants, cholestyramine
and colestipol. Unfortunately, according to the American Heart
Association, bile acid sequestrants have troublesome side effects
and require
considerable patient education to achieve compliance. A recently
introduced class of drugs used to aggressively treat elevated
LDL
levels are the synthetically derived HMG-CoA reductase inhibitors,
lovastatin (Mevacor®), pravastatin and simvastatin.
Statin drugs are among the most potent lipid-lowering agents currently
available. Statin drugs lower cholesterol levels by inhibiting the
production HMG-CoA reductase, resulting in a decrease in cholesterol
synthesis in the liver.(2) To compensate for the resulting reduction
of cholesterol production the liver increases absorption of LDL
cholesterol, further contributing to an overall reduction in blood
LDL cholesterol levels.
Statin therapy has contributed to the substantial
decrease in CHD morbidity and mortality in recent years, as documented
in a number of controlled clinical trials.(3) Although statin therapy
was first used for patients suffering from severe hypercholesterolemia,
more recent trials have shown benefit for patients with moderately
elevated cholesterol. In addition to improvements in lipid profile,
statins appear to confer other benefits, including improved endothelial
function, decreased platelet thrombus formation, improved fibrinolytic
activity and reduction in frequency of transient myocardial ischemia.(3,4)
While statin drugs are effective at lowering LDL cholesterol, they
have serious side effects. Statins work by inhibiting 3-hydroxy-3-methylglutaryl-coenzyme
A reductase, the enzyme involved in the biosynthesis of cholesterol
from acetyl-CoA. In 1990 Folkers and colleagues theorized that inhibition
of this key enzyme would also inhibit the intrinsic biosynthesis
of coenzyme Q10 (CoQ10), a central compound in the mitochondrial
respiratory chain. The researchers stated that "If lovastatin
were to reduce levels of CoQ10, this reduction would constitute
a new risk of cardiac disease, since it is established that CoQ10
is indispensable for cardiac function."
The researchers reported on protocols involving
five hospitalized patients, 43-72 years old, and one volunteer who
was monitored for CoQ10 and cholesterol levels and cardiac function.
All data from the protocols revealed that lovastatin does indeed
lower levels of CoQ10. The five hospitalized patients taking lovastatin
evidenced an increase in cardiac disease from lovastatin, which
was life-threatening for patients having class IV cardiomyopathy
before lovastatin or after taking lovastatin. Oral administration
of CoQ10 increased blood levels of CoQ10 and was generally accompanied
by an improvement in cardiac function.
The researchers concluded that "Although
a successful drug, lovastatin does have side effects, particularly
including liver dysfunction, which presumably can be caused by the
lovastatin-induced deficiency of CoQ10."(5)
In a second study designed to evaluate the effects
of statins on coenzyme-Q10 serum level and mitochondrial function,
researchers measured ubiquinone serum level and blood lactate/pyruvate
ratios in 80 patients diagnosed with hypercholesterolemia.9 At the
end of the study lactate/pyruvate ratios were significantly higher
in the patients treated with statins than in the control group,
indicating reduced mitochondrial function. Additionally, Co-Q10
serum levels were lower in the statin treated group (0.75 mg l-l)
than in the control (0.95 mg l-l).
Statin drugs are also expensive to use—depending
on the drug and dosage, statin therapy can cost between $63-$228
per month.(6)
To deal with the prohibitive cost of statins, researchers in China
have been examining traditional Chinese medicinal compounds in a
search for more affordable alternatives to controlling cholesterol
levels.(2) One of the most promising prospects was a natural food
product called red yeast rice. Red yeast rice is used extensively
in Chinese cooking as a flavoring agent and food coloring for dishes
such as tofu, Peking duck and Chinese spareribs. Also known as Hung-chu
or Hong-Qu, red yeast rice is manufactured by fermenting rice with
a specific strain of yeast called Monascus purpureus, Went. Red
yeast rice has been revered for its health-enhancing properties
for over two thousand years—records dating back to the Ming
Dynasty (1368-1644) describe red yeast's role in promoting a healthy
cardiovascular system by improving blood circulation and reducing
clotting.(7)
Chinese researchers discovered that red yeast
rice contains a number of compounds—the most abundant of which
is lovastatin, the same cholesterol-lowering ingredient found in
pharmaceutical statins such as Mevacor—that act as HMG-CoA
reductase inhibitors. Researchers also reported finding a number
of naturally occurring unsaturated fatty acids that appear to promote
lower triglyceride levels while increasing HDL levels.
Red yeast rice's ability to reduce serum cholesterol levels has
been demonstrated in a number of clinical trials in China, and more
recently in the U.S. In China, researchers conducted a randomized,
single-blind trial with 502 patients diagnosed with hyperlipidemia.2
Patients either had a serum total cholesterol (TC) of at least 230
mg/dL, LDL of at least 130 mg/dL, or tryglycerides (TG) of 200-400
mg/dL. All patients also had HDL levels less than or equal to 40
mg/dL for men, or HDL less than or equal to 45 mg/dL for women.
Patients were randomized into one of four groups:
three treatment groups (A, C, and D), and a control (B). Patients
in the treatment groups were given 600 mg of red yeast rice twice
a day (1200 mg/d) Patients in the control group were given Gynostemma
pentaphylla, a Chinese herb with putative hypolipidemic properties,
three tablets twice a day (1200 mg/d). 446 patients completed
the
study.
After four weeks of therapy with red yeast rice,
improvements in lipid chemistry showed substantial benefit:
- LDL levels of the treatment group declined
an average of 24.6% versus only 6.3% in the control group.
- Serum triglyceride levels declined ,an average
of 19.8% in the treatment group versus 9.2% in controls.
- HDL levels increased by 12.8% in the treatment
versus only 4.9% in the control group.
- Total cholesterol levels decreased significantly
by 17.1% in the test subjects, compared to a drop in the control
group of only 4.8%.
Benefits continued to accrue over the course of
the eight week study, with patients in the treatment group achieving
an average reduction in total cholesterol of 22.7% (p-value <
0.001) versus a 7% average reduction in the control group. LDL reduction
was significantly greater for the treatment group, being reduced
by 30.9%. Triglycerides were reduced by 34.1% in the treatment group
versus 12.8% and in the control groups. HDL increased by 19.9% versus
only 8.4% in the control group.
The authors of the study stated that red yeast
rice is a "highly effective and well tolerated dietary supplement
that can be used to regulate elevated serum cholesterol and triglycerides."
In the first American study on red yeast rice,
researchers recorded benefits consistent with the scientific studies
in China. Dr. David Heber of the University of California at Los
Angeles published the report in the American Journal of Clinical
Nutrition. The study, a 12-week, double-blind, placebo-controlled
study conducted at UCLA, involved 83 volunteers taking a proprietary
red yeast rice supplement. Main outcome measures were total cholesterol,
total triacylglycerol, and HDL and LDL cholesterol measured at weeks
8, 9, 11 and 12. Total cholesterol concentrations decreased significantly
in the red yeast rice-treated group compared with the placebo-treated
group. LDL cholesterol and total triacylglycerol were also reduced
with the supplement.8
"LDL (bad cholesterol) levels dropped 15
percent among patients taking the red yeast supplement over an eight-week
period," said Dr. Heber. "A 15 percent reduction is highly
significant. Individuals following a very strict diet—without
taking a cholesterol lowering supplement—can only expect to
lower their cholesterol by 10 percent at most."
A second study, directed by Dr. James Rippe of
Tufts University School of Medicine in Boston, found similar results.
Doctors in 12 medical practices across the country put 233 people
on red yeast rice for eight weeks. Their cholesterol levels fell
from an average of 242 to 206.
Red yeast has been proven effective in a number of clinical trials
at promoting healthy cholesterol levels in subjects with total serum
cholesterol greater than 200 mg/dl. and triglyceride levels greater
than 200 mg/dl. Lovastatin, the main active ingredient in red yeast
rice, has been extensively researched, the results of which lend
credible support for the efficacy of red yeast rice in maintaining
a healthy cardiovascular system. Red yeast has been proven as effective
as pharmaceutical statin drugs, such as Mevacor, but at about one-fifth
the cost, and is available without a prescription.
Human studies with red yeast rice extracts show them to be well-tolerated.
A small number of side effects, including heartburn, flatulence
and dizziness, resolved upon discontinuation of the product.
References
1. National Health and Nutrition Examination
Study III (NHANES III, 1988–94) (CDC) NCHS.
2. Wang J, Zongliang L, 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. Current
Therapeutic Research 1997;58(12):964-78.
3. Farmer JA. Aggressive lipid therapy in the statin era. Prog Cardiovasc
Dis 1998;41:71-94.)
4. Current and future treatment of hyperlipidemia: the role of statins.
Farnier M, Davignon J. Am J Cardiol 1998 Aug 27 82:4B 3J-10J
5. Lovastatin decreases coenzyme Q levels in humans. Folkers K,
Langsjoen P, Willis R, Richardson P, Xia LJ, Ye CQ, Tamagawa H.
Proc Natl Acad Sci U S A 1990 Nov 87:22 8931-4
6. Perreault S, et al. Treating hyperlipidemia for the primary prevention
of coronary disease. Are higher doses of lovastatin cost-effective?
Arch Intern Med 1998;158:375-381.)
7. Heber D. Natural Remedies for a Healthy Heart. Garden City Park,
NY: Avery; 1998.)
8. Cholesterol-lowering effects of a proprietary Chinese red-yeast-rice
dietary supplement. Heber D, Yip I, Ashley JM, Elashoff DA, Elashoff
RM, Go VL, Am J Clin Nutr 1999 Feb 69:2 231-6
9. Lipid-lowering drugs and mitochondrial function: effects of HMG-CoA
reductase inhibitors on serum ubiquinone and blood lactate/pyruvate
ratio. De Pinieux G, etal. Br J Clin Pharmacol 1996 Sep 42:3 333-7. |