A fascinating new study adds to the growing body of literature showing that green tea can impact weight gain and be an important tool in the fight against obesity.

In the current study, published in Obesity, obese mice that were fed a weight-gaining diet put on significantly less weight when they were supplemented with green tea extract.

The mice were allowed to eat as much as they wanted anytime they wanted. Their diet consisted of unlimited amounts of the mice equivalent of McDonald’s, with everything on the menu supersized.

In addition to this Vegas buffet of mice chow, one group of mice were fed EGCG (epigallocatechin-3-gallate), the polyphenol in green tea that has been found to have the most profound effect on metabolism and weight. The other group was not.

The group getting the EGCG supplement gained weight at about 45% the rate of the non-supplemented mice.

“There’s no difference in the amount of food the mice are eating”, Lambert told Science Daily. “The mice are essentially eating a milkshake, except one group is eating a milkshake with green tea”.

Lambert estimates that a person would need to drink ten cups of green tea each day to match the amount of EGCG used in the study. But remember, most estimates of how much EGCG are in one cup of brewed tea range from 5-40 mg, so at that rate, sure, ten cups would give you anywhere from 50 to 400 mg of EGCG.

One single capsule of EGCG (green tea extract (EGCG) provides 250 mg, the amount you’d get from 10 cups providing 25 mg each, or approximately 6 cups providing 40 each.

The researchers in this study also noted that fecal fat excretion was 30% higher in the EGCG mice. The belief is that EGCG somehow reduces production in the pancreas of the fat-digesting enzyme lipase so that some of the fat you eat isn’t actually digested. (This is exactly how the weight loss pill ALLI works).

“There seems to be two prongs to this”, said Lambert. “First, EGCG reduces the ability to absorb fat and, second, it enhances the ability to use fat”.

The excellent thing about drinking green tea and taking green tea supplements is that even if they don’t help you lose weight—and there’s no reason they shouldn’t!—they do a million other good things for you.

Green tea (and green tea extract, EGCG) have been shown to have preventive effects in obesity, insulin resistance, and hypertension. Green tea polyphenols like EGCG have been shown to have a role in cancer prevention. And green tea itself contains a nice relaxing compound called Theanine which is actually used as a drug in Japan for anxiety and which is available as a supplement.

There aren’t too many supplements you can take that can positively impact your weight and have as “side effects” anti-inflammatory, anti-oxidant, anti-insulin resistance, anti-hypertension and anti-cancer activity!