Physical exercise, diet and supportive counseling are the first steps of any weight-loss program. But sometimes that's not enough to take large amounts of weight off, and keep it off, doctors say. 13/Ocean/Corbis hide caption

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Woman weighing herself. ImageZoo/Corbis hide caption

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Just knowing that someone is obese doesn't mean they would benefit from bariatric surgery, doctors say. iStockphoto.com hide caption

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Evidence is growing that bariatic surgery reduces health risks of obesity. Life in View/Science Source hide caption

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