PHILADELPHIA, Jan. 4 (UPI) -- U.S. researchers Tuesday said a review of popular diets finds except for Weight Watchers, there little evidence to support claims they work.
The University of Pennsylvania study, published in the Annals of Internal Medicine, looked at Weight Watchers, Jenny Craig, L A Weight Loss, Health Management Resources, OPTIFAST, eDiets.com, Overeaters Anonymous and Take Off Pounds Sensibly. Researchers reviewed clinical trials and Web sites, talked with representatives and searched medical databases for information.
In looking at clinical trials, Weight Watchers had the strongest studies to support its claims, and one Weight Watchers diet was most successful of all diets studied -- with an average loss of 3.2 percent of initial weight -- or about 5 pounds -- at two years into the program.
One trial and several case studies of medically supervised very-low-calorie diet programs found people lost from 15 percent to 25 percent of their initial weight but had a high probability of regaining at least 50 percent or more of the lost pounds within a year or two.
The researchers said commercial interventions available over the Internet and organized self-help programs produced minimal weight loss.
