GUNMA, Japan—Black tea extract suppressed weight gain and fat levels in a recent mice study (doi:10.1016/j.nut.2010.01.019). The Japanese researchers found that black tea extract prevented diet-induced obesity by inhibiting intestinal lipid absorption. They also suggested that the major active component in the black tea extract was the polyphenols.
Using black tea extract, researchers from the Kirin Beverage Company Ltd., Gunma, Japan, prepared a polymerized polyphenol fraction (BTP), and fed it to Male Wistar rats at a concentration of 500 or 1,000 mg/kg body weight. Researchers then measured their plasma lipid levels. Additionally, female mice were fed either a standard or high-fat diet supplemented with 1-percent or 5-percent black tea extract for eight weeks, and changes in body weight were examined.
Both the BTP and black tea extract inhibited pancreatic lipase activity. The black tea extract suppressed increases in rat plasma triglyceride levels in a dose-dependent manner. Furthermore, administration of the 5 percent black tea extract suppressed increases in body weight (P<0.05), parametrial adipose tissue mass and liver lipid content (reduced to 56.9 percent and 81.7 percent of control mice, respectively, P<0.05) in mice fed a high-fat diet.