Extracts from green tea can stop the build-up of fatty deposits in the liver. The incidence of nonalcoholic fatty liver disease (NAFLD) has risen along with the obesity epidemic. Green tea extract (GTE) has been shown to inhibit intestinal lipid absorption and may regulate hepatic lipid accumulation. A US team fed groups of genetically obese and lean mice a diet containing zero, 1%, or 2% green tea extract (GTE) for six weeks. At the end of the study, the obese mice fed GTE weighed 23-25% less than obese mice fed the non-supplemented diet. In addition, lean mice fed GTE weighed 11-20% less those on the non-supplemented diet.

Measurements of circulating levels of the enzymes alanine aminotransferase and aspartate aminotransferase, which act as markers of liver damage, showed that GTE-supplementation was associated with 30-41% and 22-33% lower activities, respectively. No significant differences were observed in food intake between lean and obese animals in any group, suggesting that GTE works by decreasing intestinal fat absorption or altering liver fat metabolism.

Green tea extract protects leptin-deficient, spontaneously obese mice from hepatic steatosis and injury. J Nutr. 2008 Feb;138(2):323-31.