Ineffectiveness of commercial weight-loss programs for achieving modest but meaningful weight loss: Systematic review and meta-analysis

J Health Psychol. 2017 Oct;22(12):1614-1627. doi: 10.1177/1359105317705983. Epub 2017 May 10.


This study collates existing evidence regarding weight loss among overweight but otherwise healthy adults who use commercial weight-loss programs. Systematic search of 3 databases identified 11 randomized controlled trials and 14 observational studies of commercial meal-replacement, calorie-counting, or pre-packaged meal programs which met inclusion criteria. In meta-analysis using intention-to-treat data, 57 percent of individuals who commenced a commercial weight program lost less than 5 percent of their initial body weight. One in two (49%) studies reported attrition ≥30 percent. A second meta-analysis found that 37 percent of program completers lost less than 5 percent of initial body weight. We conclude that commercial weight-loss programs frequently fail to produce modest but clinically meaningful weight loss with high rates of attrition suggesting that many consumers find dietary changes required by these programs unsustainable.

Keywords: commercial; dieting; obesity; weight-loss program.

Publication types

  • Meta-Analysis
  • Review
  • Research Support, Non-U.S. Gov't
  • Systematic Review

MeSH terms

  • Humans
  • Overweight / therapy*
  • Treatment Outcome
  • Weight Loss*
  • Weight Reduction Programs*