New research suggests that if you want to lose weight, don't try to do it alone.

According to research in the journal Obesity, "Group-based weight-loss treatment produced weight loss, whether delivered by a professional or peer counselor," said study author Angela Marinilli Pinto, assistant professor of psychology at Baruch College of the City University of New York. "When people are in a group with others on the same journey, they feel there is that element of, 'OK, this worked for him or her, perhaps it will work for me. Perhaps I can give it a try.'"

Pinto and her team randomly assigned 141 overweight or obese men and women to one of three groups:

  • Behavioral weight-loss treatment from a health professional.
  • Weight Watchers.
  • Combined treatment.

Pinto said she chose Weight Watchers because it is the largest commercial program in the United States. It is also oriented to behavior change and included information on modifying the diet and increasing physical activity to lose weight and maintain the loss.

The findings were a surprise. At 48 weeks, the researchers found no evidence that adding brief treatment led by professionals, and then transitioning to the Weight Watchers program, improved results.

At 48 weeks, those in the professionally led group lost 11.9 pounds, while those only in Weight Watchers lost more (13.2 pounds). The combination group lost the least -- 7.9 pounds, on average.

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