Certain religions, including Judaism and Islam also impose restrictions on diet, but these are not usually thought of as 'dieting'.
Most typically "dieting" means eating in a carefully planned way to in order to reduce excess body fat. In this sense, there are a number of so-called diets that can be used as part of a regimen of dieting. Also in this sense, excessive dieting is related to [anorexia nervosa]? and bulimia?, which are life-threatening conditions. [Weight Watchers]? is a well-known organization in the United States that supports weight loss efforts.
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