Food combining (also known as trophology) is a term for a nutritional approach that advocates specific combinations of foods as central to good health and weight loss (such as not mixing carbohydrate-rich foods and protein-rich foods in the same meal). The best-known food-combining diet is the Hay Diet; Hay lost 30 pounds in 3 months when he implemented his research. One randomized controlled trial of food combining has been performed, and found no evidence that food combining was any more effective than a "balanced" diet in promoting weight loss.
Food combining adherents believe that watermelon and other melons should be consumed separately from other foods. 
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