Clinician Article

Efficacy of commercial weight-loss programs: an updated systematic review.

  • Gudzune KA
  • Doshi RS
  • Mehta AK
  • Chaudhry ZW
  • Jacobs DK
  • Vakil RM, et al.
Ann Intern Med. 2015 Apr 7;162(7):501-12. doi: 10.7326/M14-2238. (Review)
PMID: 25844997
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  • Internal Medicine
    Relevance - 6/7
    Newsworthiness - 6/7
  • Special Interest - Obesity -- Physician
    Relevance - 6/7
    Newsworthiness - 6/7
  • Family Medicine (FM)/General Practice (GP)
    Relevance - 6/7
    Newsworthiness - 5/7
  • General Internal Medicine-Primary Care(US)
    Relevance - 6/7
    Newsworthiness - 5/7
  • Public Health
    Relevance - 6/7
    Newsworthiness - 5/7


BACKGROUND: Commercial and proprietary weight-loss programs are popular obesity treatment options, but their efficacy is unclear.

PURPOSE: To compare weight loss, adherence, and harms of commercial or proprietary weight-loss programs versus control/education (no intervention, printed materials only, health education curriculum, or <3 sessions with a provider) or behavioral counseling among overweight and obese adults.

DATA SOURCES: MEDLINE and the Cochrane Database of Systematic Reviews from inception to November 2014; references identified by program staff.

STUDY SELECTION: Randomized, controlled trials (RCTs) of at least 12 weeks' duration; prospective case series of at least 12 months' duration (harms only).

DATA EXTRACTION: Two reviewers extracted information on study design, population characteristics, interventions, and mean percentage of weight change and assessed risk of bias.

DATA SYNTHESIS: We included 45 studies, 39 of which were RCTs. 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. Nutrisystem resulted in at least 3.8% greater weight loss at 3 months than control/education and counseling. Very-low-calorie programs (Health Management Resources, Medifast, and OPTIFAST) resulted in at least 4.0% greater short-term weight loss than counseling, but some attenuation of effect occurred beyond 6 months when reported. Atkins resulted in 0.1% to 2.9% greater weight loss at 12 months than counseling. Results for SlimFast were mixed. We found limited evidence to evaluate adherence or harms for all programs and weight outcomes for other commercial programs.

LIMITATION: Many trials were short (<12 months), had high attrition, and lacked blinding.

CONCLUSION: Clinicians could consider referring overweight or obese patients to Weight Watchers or Jenny Craig. Other popular programs, such as Nutrisystem, show promising weight-loss results; however, additional studies evaluating long-term outcomes are needed.


PROSPERO: CRD4201-4007155).

Clinical Comments

Family Medicine (FM)/General Practice (GP)

Weight loss, even over 12 months, is a poor predictor of long-term sustained loss. Cost of Jenny Craig at over $500/month is prohibitive for many.

Family Medicine (FM)/General Practice (GP)

I often recommend Weight Watchers as a practical and effective means of long-term weight loss as it is based on recommendations from Canada`s Food Guide, and does not require the purchase of special foods that are often quite expensive (as is the case with Jenny Craig).

Family Medicine (FM)/General Practice (GP)

This is helpful information in that it attempts to demonstrate the actual benefits of these programs. As always, no long-term study results are available.

Internal Medicine

Always good to have the facts about these programs for patients who inquire about them.

Public Health

This systematic review does not show clear efficacy of commercial and proprietary weight-loss programs for obesity treatment. Most pooled RCTs evaluated short-term outcomes. The study is well-designed and carefully executed.

Special Interest - Obesity -- Physician

Interesting manuscript with conclusions that may help obesity physicians to suggest one of many commercial weight loss programs on the market.

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