Like all industries, the herbal weight-loss business moves in cycles. Less than a decade ago, the stimulant herb ephedra was one of the stars of the scene. It sped up metabolism and weight loss, but it also raised the heart rate and, in some cases, caused strokes and heart attacks.
The Food and Drug Administration banned ephedra supplements in 2004, setting off an industrywide scramble to find another herb that could take its place. For now, the winner seems to be green tea. Its reputation as a healthful, revitalizing beverage goes back thousands of years, and it has recently started showing up in a wide range of weight-loss supplements.
Green tea naturally contains caffeine, a common ingredient in all sorts of weight-loss products. It also contains EGCG, a strong antioxidant that seems to encourage cells throughout the body to burn extra calories. In other words, it seems to be "thermogenic," a term that tends to get people in the weight-loss business very excited.
The Mega-T Green Tea Dietary Supplement from CCA Industries is sold at drugstores everywhere. Each caplet contains enough green tea extract to provide 90 milligrams of EGCG and 50 mg. of caffeine. The caplets also contain chromium, calcium, Hoodia gordonii cactus and (in one version) acai fruit, among other things. Users are instructed to take one caplet twice a day with a meal and a glass of water. A package of 90 caplets costs about $16.
Metabolife — a former leader in the ephedra market that filed for bankruptcy in 2005 amid a series of legal problems — is back in the weight-loss game with Metabolife Green Tea. According to its label, the supplement contains a "proprietary blend" that includes green tea, garcinia (a source of hydroxycitric acid) and guarana (a source of extra caffeine). The label doesn't specify how much green tea, caffeine or EGCG is in each tablet. Users are told to take two or three capsules a day about an hour before meals. A bottle of 90 capsules costs about $25.
Each tablet of Green Tea Slim from Mason Vitamins contains 60 mg. of EGCG along with chromium and apple cider vinegar, among other ingredients. Users are instructed to take one tablet two or three times a day with meals. A bottle of 60 tablets costs about $6.
CCA Industries, MetaboLife and Mason Vitamins all declined the chance to comment on their products.
The label for Mega-T Green Tea Dietary Supplement says that users can "lose up to 20 pounds." The package clarifies with an asterisked note that such results would occur "over a period of time with diet and exercise plan." According to the site, the supplement is "formulated to help you achieve your weight loss goals."
The Metabolife website says that the supplement "helps boost the body's metabolism, making it easier to burn unwanted calories."
The label for Green Tea Slim says the supplement "fights cravings and enhances metabolism" while promoting "thermogenic action."
The bottom line
Green tea really does seem to speed up metabolism, but recent studies show that the resulting weight loss is modest, bordering on trivial, says Craig Coleman, associate professor of pharmacy practice at the University of Connecticut in Storrs. "It sounds like it should work, but when the rubber hits the road in clinical trials, it doesn't really pan out."
Coleman co-authored a 2009 review of 15 studies on green tea and weight loss. On average, subjects who consumed green tea products lost an extra 1 to 3 pounds compared with those who took a placebo. Study participants generally consumed 300 mg. or more of EGCG every day, and the length of the studies ranged from three to 24 weeks. Because of such meager results, Coleman says, he "would not recommend patients take green tea extract in any form for weight loss."
But even modest weight loss can be a positive step, says Arpita Basu, assistant professor of nutritional sciences at Oklahoma State University in Stillwater. Basu was the lead author of a 2010 study of 35 obese people who consumed either 4 cups of strong green tea, two capsules of green tea extract (totaling 460 mg. of EGCG) or two placebo pills every day for eight weeks.
Subjects drinking green tea or taking green tea supplements lost an extra 5.5 pounds (2.5 kilograms) and 4.9 pounds (1.9 kg.), respectively, compared with the subjects who didn't consume any green tea. Reporting in the Journal of the American College of Nutrition, the researchers speculated that the weight-reducing power of green tea might be especially strong in people who are already obese.
Nobody should count on green tea alone to help them reach a healthy weight, but it could be a helpful part of a more comprehensive weight-loss program that includes diet and exercise, Basu says. Even if it didn't help shed a single pound, the antioxidants in green tea might help lower the risk of heart disease, she adds.
Basu is leery of products that pack all sorts of other active ingredients along with green tea, though. Instead, she suggests that people just brew a cup of fresh tea at home. "It's cheaper and safer," she says.
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