The easier a diet is to follow, the better the odds of sticking to it. So user-friendliness was one of the factors experts considered in rating the popular programs on this list. Is the diet filling and tasty? Does it impose stringent requirements such as eating a certain number of times per day? Are unique foods required? The experts put Weight Watchers at the top, viewing it as flexible, tasty, and allowing plenty of eating throughout the day.
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