Consumer Reports rated each diet on nutritional quality and looked at published studies to find out how much weight people lost on these diets and how well they were able to stick to them.
Weight Watchers recently revised its system that assigns points to every food you eat. It now puts even more emphasis on filling, good-for-you foods such as lean protein, fruits, and vegetables. But research on the program hasn't been published yet.
The high-fat Atkins diet got the lowest score for nutrition from Consumer Reports. And Slim-Fast, with its branded shakes and breakfast and lunch bars, had the worst long-term dropout rate.
Far better was Jenny Craig, which consists of prepackaged meals supplemented with fruits, vegetables, and other foods. It beat out all the other diets and had excellent nutrition and a very low dropout rate, based on a study published in the Journal of the American Medical Association. More than 90 percent of participants were able to stay on the diet for at least two years, and they lost an average of 8 percent of their starting weight.
Jenny Craig's annual membership fee is $400, although there are often special deals. The fee includes weekly counseling sessions, but the packaged food costs extra.
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