What it is: Green tea is a minimally processed tea that contains high concentrations of a plant antioxidant called epigallocatechin gallate, or EGCG, which may help with weight loss.
How it works: “EGCG blocks the body’s ability to digest fat,” says Josh Lambert, an associate professor of food science at Pennsylvania State University, in University Park. The caffeine in green tea may help trim you down, too: A 2011 synopsis of studies published in the journal Obesity Reviews found that people who consumed at least two cups a day of caffeinated green tea lost three pounds in 12 weeks without changing their diets.
Good to know: Steep tea for two to five minutes and drink two or more cups a day to reap the weight-loss benefits. If the caffeine disturbs your sleep (green tea packs 24 to 40 milligrams per eight ounces, or about a quarter of the amount found in most coffee), consume the last cup at least four hours before bedtime, says Jeffrey Blumberg, Ph.D., the director of the Antioxidants Research Laboratory at Tufts University, in Boston.