Mar. 26, 1999 ORLANDO, Fla, March 25 -- The spice that gives Peking duck its distinctive red color seems to lower blood cholesterol, two research teams reported today at the American Heart Association's epidemiology and prevention meeting.
In a study conducted in China, an extract of the red yeast fermented on rice, which is sold under the name of Cholestin, reduced total blood cholesterol by nearly 26 percent in elderly patients after eight weeks of treatment, says the study's lead author, Joseph Chang, Ph.D., vice president of clinical affairs at Pharmanex, Inc. The Simi Valley, Calif., company imports the dietary supplement to the United States.
"Cholestin also reduced 'bad' cholesterol or low-density lipoprotein cholesterol (LDL) by 32.8 percent and decreased by 19.9 percent triglycerides, a type of blood fat associated with increased risk for heart disease," says Chang.
The average total cholesterol level of study participants was 225 milligrams/deciliter (mg/dL); average LDL was 160 mg/dL and average triglyerides were 250 mg/dL. LDL is called the "bad" cholesterol because it collects in the blood vessels to form plaque that can block blood flow, triggering a heart attack or stroke. Individuals who did not receive the supplement had reductions of total blood cholesterol and LDL of about 7 percent, says Chang.
James Rippe, M.D., associate professor of medicine at Tufts University School of Medicine in Boston, reports similar results in a second study that was conducted in 12 medical centers and funded by Pharmanex. He reports that after eight weeks on Cholestin, individuals had a 16.4 percent drop in total blood cholesterol. Their LDL decreased by 21 percent, and HDL-cholesterol, the "good" cholesterol, increased by 14.6 percent. HDL cholesterol is called the "good" cholesterol because it helps remove the "bad" cholesterol from the blood. The average cholesterol levels for this group were 242 mg/dL; average LDL was 158 mg/dL and the average HDL was 50 mg/dL.
"In China, the red yeast is known to promote healthy heart function," says Rippe.
He speculated that the differences in results between the Chinese and Boston studies could be due to the fact the Chinese study used a more concentrated red yeast than that found in Cholestin.
"As a natural substance there are hundreds of potentially active ingredients in Cholestin that could have contributed to the cholesterol lowering. Cholestin contains a range of HMG-CoA reductase inhibitors that probably contribute to the effect," Rippe say. "The Chinese study participants received approximately 13.5 milligrams of HMG-CoA reductase inhibitors each day in the Cholestin preparation that they took, while the participants in the Boston study received about 9.6 mg per day," according to Rippe.
Most of the cholesterol that circulates in the blood does not come from dietary cholesterol but is instead manufactured by the liver. HMG CoA reductase is an enzyme found in the liver that controls cholesterol production in the body. By inhibiting that enzyme, red yeast reduces the body's cholesterol output, according to Rippe.
"Although red yeast fermented on rice is used to spice traditional Chinese food, such as Peking duck and spareribs, this is not an efficient way to consume the substance," says Rippe. "The capsule form of red yeast rice contains a more consistent amount of the active ingredients than the amount people in China obtain from these sources in their diet."
The capsule form of red yeast did not cause significant side effects, the researchers say.
Chang's colleague, J. S. Zhu, director of clinical pharmacology at Pharmanex in Beijing, says, of the 70 patients in his study, one dropped out because of headaches and four other individuals discontinued the study because of travel demands.
Eighteen percent of the men and women in the Boston study reported mild to moderate symptoms, mostly mild gastrointestinal problems or headaches, and 16 of the 187 individuals left the study early, says Zhu. "To put it in perspective, that is an extremely low number in general and shows that Cholestin causes few side effects," he adds.
Thomas A. Pearson, M.D., Ph.D., chairman of American Heart Association's population science committee and chairman of community and preventive medicine at the University of Rochester School of Medicine, Rochester, NY, says, "The results of these two studies are promising. In the future, the red yeast rice may provide clinicians with another tool to lower LDL cholesterol. The substance certainly merits additional study. However, too little is known to make scientifically sound statements about the safety and effectiveness of this substance to make a public health recommendation about its use at present.
"In the meantime, the American Heart Association continues to advise individuals to try to lower high blood cholesterol with a diet that is low in saturated fat and rich in fruits, vegetables and whole grains," says Pearson. "If diet alone does not bring the cholesterol levels under control, treatment with several types of medications, including statin drugs that have been comprehensively studied, are a second step in treatment options."
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