Research

Adherence

Weight Watchers, a nonmedical commercial program, produces modest weight loss (3.2% at 2 years) with higher adherence than self-help interventions, but evidence for other major commercial programs (Jenny Craig, LA Weight Loss) is suboptimal.

Weight Watchers can help you lose about 3% of your body weight over 2 years, which is modest but better than self-help. It works through weekly group support and behavioral counseling. It's affordable ($12/week) and accessible, making it a good choice for long-term maintenance if you value social support over rapid results.

ModerateQualifiesMEDIUM confidence
Of 3 randomized, controlled trials of Weight Watchers, the largest reported a loss of 3.2% of initial weight at 2 years... With the exception of 1 trial of Weight Watchers, the evidence to support the use of the major commercial and self-help weight loss programs is suboptimal.
Adam Gilden Tsai et al. · Annals of Internal Medicine · 2005

Why this rating

Based on 3 RCTs, but one was small (n=48) and another had no follow-up; the largest trial had 27% attrition.

Source

Systematic Review: An Evaluation of Major Commercial Weight Loss Programs in the United States

Adam Gilden Tsai et al. · Annals of Internal Medicine · 2005

DOI 10.7326/0003-4819-142-1-200501040-00012

systematic_reviewCited 812×
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DOI resolved against Crossref · corpus check 2026-06-10

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