Antioxidant compounds in green tea could help promote exercise-induced abdominal fat loss, according to a new study from the American Society of Nutrition. Researchers recruited over 100 healthy normally sedentary adults, aged 21 to 65, with a mean BMI of 32 (moderate obesity). Subjects were randomly assigned to drink 500ml per day of either a beverage providing 625mg catechins, or a similar control drink (containing added caffeine to match the caffeine content of the catechin beverage).

They continued their usual food/energy intake, and committed to 180 minutes of moderate-intensity physical activity per week, including at least three supervised exercise sessions. Changes in fat mass and waist circumference did not differ between the catechin and control groups. However, percentage changes in total abdominal fat area, subcutaneous abdominal fat area, and fasting serum triglycerides were greater in the catechin group.

The authors conclude that consumption of green tea catechins enhances exercise-induced changes in abdominal fat and serum triglycerides. (Green tea catechin consumption enhances exercise-induced abdominal fat loss in overweight and obese adults. J Nutr. 2009 Feb;139(2):264-70. Epub 2008 Dec 11).

A meta-analysis of studies assessing the association of tea consumption with the risk of type-2 diabetes has been carried out by Chinese researchers. The authors identified nine English-language cohort studies, including 324,141 participants and 11,400 incident cases of type-2 diabetes, with follow-up ranging from five to 18 years.

Their meta-analysis indicated that tea consumption >= four cups per day was associated with a lower risk of type-2 diabetes. (Tea consumption and risk of type 2 diabetes: a meta-analysis of cohort studies. J Gen Intern Med. 2009 May;24(5):557-62. Epub 2009 Mar 24).