Weight loss supplements are a $2.4 billion industry in the United States, but do they work? Oregon State University researcher Melinda Manore reviewed information surrounding hundreds of weight loss supplements and found no evidence that any single product results in significant weight loss. She also found that many have detrimental health benefits. Green tea and a few other products, however, were revealed to have a modest weight loss benefit of 3-4 pounds (2 kilos). It is important to know that most of the supplements were tested as part of a reduced calorie diet.
"For most people, unless you alter your diet and get daily exercise, no supplement is going to have a big impact," Manore said. Manore, professor of nutrition and exercise sciences at OSU, is on the Science Board for the President's Council on Fitness, Sports and Nutrition. Her research is focused on the interaction of nutrition and exercise on health and performance. "Adding fiber, calcium, protein and drinking green tea can help," Manore said. "But none of these will have much effect unless you exercise and eat fruits and vegetables."
Source: International Journal of Sport Nutrition and Exercise Metabolism