A longer-term study examined the effects of 12 weeks of drinking green tea (690 mg total catechins/day of which 136 mg was EGCG) versus placebo on weight loss and several measures of body fat in men. Men consuming the green tea had a two-fold greater weight loss (-5.3 vs -2.8 lbs) and fat loss (-3.1 vs -1.5 lbs). Compared to placebo, green tea had a dramatic four-fold greater effect on reductions in subcutaneous and visceral fat in the abdomen as measured by computed tomography imaging.
Greater fat in the abdominal region is associated with higher risk for many chronic diseases.
In another study, Japanese researchers tested the effects of supplementing with green tea on weight and fat loss. Obese men and women were randomly assigned to consume daily a drink containing 625 catechins or a control beverage for 12 weeks. They were asked to make no other changes in their diet, but all subjects were required to increase daily physical activity. The catechin group lost almost 5 pounds which was more than twice the control group who lost 2 pounds. Fat loss was also greater in the catechin group (-5.2%) versus the control (-3.5%). The most noteworthy finding was that the catechin group lost significantly more fat in the abdomen (-7.7%) compared to the control (-0.3%).
In a third study, overweight men and women were fed three meals per day in a hospital kitchen for 6 weeks. Half the subjects were randomized to a control tea group and half to a green tea group. They consumed 20 ounces of tea two times per day. The green tea contained a total of 534 mg/day of catechins, compared to 162 mg/day in the control tea. There was no body fat loss in the control group, but the green tea group lost over 4 pounds of body fat. Collectively, these studies show that green tea is an effective method for shedding fat, particularly in the mid-section.