In China, Shenyang Pharmaceutical University has a research on 102 overweight or obese people to drink 8 grams Oolong tea a day for 6 weeks. After 6 weeks, total 70% loss more than 1 kg body weight and 22% of it loss more than 3 kgs body weight, and 64% of the obese subjects and 66% of the overweight subjects lost more than 1 kg during the experiment.