Research

Adherence

Commercial weight-loss programs Weight Watchers and Jenny Craig produce statistically significant and clinically relevant greater weight loss compared to control or behavioral counseling interventions at 12 months.

If you are overweight or obese, joining a high-intensity commercial program like Weight Watchers or Jenny Craig is a clinically supported strategy for losing weight. These programs provide structure, accountability, and social support that lead to better results than trying to lose weight alone or with basic education. Expect to lose at least 2.6% more body weight with Weight Watchers and 4.9% more with Jenny Craig compared to no program after one year. While they cost money, they may be cost-effective compared to other treatments.

ModerateSupportsMEDIUM confidence
At 12 months, Weight Watchers participants achieved at least 2.6% greater weight loss than those assigned to control/education. Jenny Craig resulted in at least 4.9% greater weight loss at 12 months than control/education and counseling.
Kimberly A. Gudzune et al. · Annals of Internal Medicine · 2015

Why this rating

Moderate Risk of Bias (ROB) due to lack of blinding and variable attrition, but based on multiple RCTs.

Source

Efficacy of Commercial Weight-Loss Programs

Kimberly A. Gudzune et al. · Annals of Internal Medicine · 2015

DOI 10.7326/m14-2238

systematic_reviewCited 331×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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