Current evidence supports the efficacy of only 2 of the 141 commercial or proprietary weight-loss programs available in the United States: Weight Watchers and Jenny Craig, according to a report published online April 6 in Annals of Internal Medicine.
Physicians are increasingly called upon to refer patients to high-intensity weight-loss programs, given provisions in the Affordable Care Act and a recent joint clinical practice guideline from the American Heart Association, the American College of Cardiology, and the Obesity Society. But there are no recommendations about the relative merits of such programs. To help clinicians assess their efficacy, investigators performed a comprehensive review of the literature.
They included only programs that stressed nutrition and behavioral counseling or social support, with or without a physical activity component, because these elements have been identified as essential to weight loss. This excluded popular programs such as Ornish and Zone, and winnowed the mass of evaluable weight-loss programs to 32. Further restricting their analysis to randomized clinical trials of at least 12 weeks’ duration excluded programs such as South Beach and Ideal Protein, and reduced the analysis to 11 programs assessed in 45 studies, said Dr. Kimberly A. Gudzune , of Johns Hopkins University, Baltimore, and her associates.
The primary efficacy outcome was mean percentage of weight loss at 1 year, compared with control conditions. Pooled results from six trials showed Weight Watchers resulted in a 2.6% greater weight loss, and pooled results from three trials showed Jenny Craig resulted in a 4.9% greater weight loss. NutriSystem showed “promising” short-term results, but no studies assessed its efficacy beyond the 3-month mark. The data on all other programs, including Medifast, SlimFast, HMR, Optifast, Atkins, Biggest Loser Club, eDiets, and Lose It!, were either insufficient or of questionable quality, the investigators said (Ann. Intern. Med. 2015 April 6 [doi:10.7326/M14-2238]).
“Given these findings, it may be reasonable for clinicians to refer patients to Weight Watchers or Jenny Craig, especially if they lack the time, training, or ancillary staff to deliver behavioral counseling in their practices,” Dr. Gudzune and her associates said.
