South Beach Diet Beats Others in Keeping Weight Off

Indeed, fewer participants in the high-protein diet groups and the low glycemic index groups dropped out of the study, the researchers found.

Some experts, however, are skeptical about the results and controversies remain about the best diet plan for overall health.

Carla Roper, a research faculty member at the New York Obesity Center, downplayed the utility of dieting in weight management.

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"What we do know is that diet choice is not the definitive predictor of weight maintenance," Roper said. "Physical activity is the crucial variable in weight maintenance."

Exercise Is Important, Too

Similarly, Dr. Tim Byers, associate dean of the Colorado School of Public Health said the biggest factor in weight maintenance and overall health is physical activity, not the details of food types.

"It is not so much important what you eat after weight loss as how much you eat and how much you move," Byers said.

Although exercise is undoubtedly important for healthy living, research suggests that increasing protein and decreasing refined, processed carbohydrates will help sustain weight loss.