"These foods do fill up the stomach and increase satiety, " says Dr Garvey, keeping you from ingesting more calories later - but not burning off the calories you've already consumed.

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According to a 2001 study led by researchers at the University of Washington, Seattle, adding dextrin to a beverage can increase levels of satiety and so reduce energy intake in subsequent meals by about 72 calories.

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Pumping up foods with air also works to increase volume and promote satiety.

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