The fat-busting benefits of green tea boil down to disease-fighting compounds called catechins. One study of 240 Japanese men and women found that when subjects drank green tea containing 583 milligrams of catechins per 12-ounce cup, they dropped more weight – and inches – than those who ingested tea containing only 96 milligrams. Max your results by steeping your bag of green tea as long as possible. The darker the hue of your brew (and how bitter it is), the more catechin-rich the cup.
Consumption of green tea has been associated with a number of positive effects on health. Several studies have shown regular use of green tea can aid fat loss. Green tea is believed to augment norepinephrine, a hormone that promotes fat breakdown. Other possible benefits of green tea include decreased food intake and decreased formation of fat.
Polyphenols, the bioactive compounds in green tea, account for a third of the dry weight of the leaves. The predominant polyphenols are the catechins including epicatechin, epicatechin-3-gallate, epigallocatechin and epigallocatechin-3-gallate (EGCG). Most research has focused on EGCG as the predominant polyphenol.
German researchers recently tested the effects of EGCG rates of carbohydrate and fat oxidation. Subjects consumed either 300 mg of EGCG or placebo, supplementation with EGCG caused a shift in energy utilization from carbohydrate to fat oxidation. The effect was more pronounced after eating a meal. In the placebo trial, only 30% of the total energy burned after the meal was attributed to fat, whereas 54% of the energy burned came from fat oxidation after EGCG supplementation.
These results show supplementation with 300 mg EGCG encourages use of fat over carbohydrate as fuel, which provides a plausible mechanism to explain the anti-obesity effects of green tea.