The double-blind, randomized, controlled study included 240 men and women with high cholesterol levels in China. During the 12-week trial, participants, already on a low-fat diet, were randomly chosen to receive either a placebo or a 375 mg soft gel capsule containing green and black tea extracts enriched with the antioxidant theaflavin.
The results, reported in the June 23 issue of "Archives of Internal Medicine," amazed lead author Dr. David J. Maron, associate professor of Medicine at Vanderbilt University Medical Center.
"Personally, I was very surprised," Maron said. "I expected, if anything, a very slight cholesterol-lowering effect. But what we saw was a 16 percent reduction in low density lipoprotein (LDL) cholesterol."
Tea is the second most widely consumed beverage worldwide. In the past, several epidemiologic studies had shown that tea consumption is associated with lower cholesterol. Experiments in animals have demonstrated that green tea, black tea, and flavonoids derived from green and black teas lower cholesterol. However, previous tea-drinking experiments in humans, as well as those experiments involving the administration of green tea extract, have failed to show any effects on cholesterol.
The 375 mg capsule used in this study is an extract made up of 75 mg of theaflavins (flavonoids from black tea), 150 mg of catechins (flavonoids from green tea) and 150 mg of other tea antioxidants called polyphenols. It is equivalent to 35 cups of high-quality black tea and seven cups of green tea.
The National Cholesterol Education Program recommends eating a low-fat, low-cholesterol diet with more viscous fiber and switching from butter to margarine with the natural plant compound stanol, as the initial therapy for lowering LDL cholesterol in people without heart disease, said
'"/>
Contact: Clinton Colmenares
clinton.colmenares@vanderbilt.edu
615-322-4747
Vanderbilt University Medical Center
23-Jun-2003