title: A systematic review of commercial weight loss programmes' effect on glycemic outcomes among overweight and obese adults with and without type 2 diabetes mellitus.
abstract: We examined the glycemic benefits of commercial weight loss programmes as compared with control/education or counselling among overweight and obese adults with and without type 2 diabetes mellitus (T2DM).
  
  
  
  We searched MEDLINE, Cochrane Database of Systematic Reviews, and references cited by individual programmes. We included randomized controlled trials of ≥12 weeks duration. Two reviewers extracted information on study design, population characteristics, interventions, and mean changes in haemoglobin A1c and glucose.
  
  
  
  We included 18 randomized controlled trials. Few trials occurred among individuals with T2DM. In this population, Jenny Craig reduced A1c at least 0.4% more than counselling at 12 months, Nutrisystem significantly reduced A1c 0.3% more than counselling at 6 months, and OPTIFAST reduced A1c 0.3% more than counselling at 6 months. Among individuals without T2DM, few studies evaluated glycemic outcomes, and when reported, most did not show substantial reductions.
  
  
  
  Few trials have examined whether commercial weight loss programmes result in glycemic benefits for their participants, particularly among overweight and obese individuals without T2DM. Jenny Craig, Nutrisystem and OPTIFAST show promising glycemic lowering benefits for patients with T2DM, although additional studies are needed to confirm these conclusions. © 2016 World Obesity.
authors.affiliation: The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Z W
authors.initials: ZW
authors.lastname: Chaudhry
authors.affiliation: The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: R S
authors.initials: RS
authors.lastname: Doshi
authors.affiliation: The Johns Hopkins Bayview Medical Center, Baltimore, MD, USA.
authors.forename: A K
authors.initials: AK
authors.lastname: Mehta
authors.affiliation: The University of Maryland School of Medicine, Baltimore, MD, USA.
authors.forename: D K
authors.initials: DK
authors.lastname: Jacobs
authors.affiliation: The Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.|Rutgers Robert Wood Johnson Medical School, Piscataway, NJ, USA.
authors.forename: R M
authors.initials: RM
authors.lastname: Vakil
authors.affiliation: The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: C J
authors.identifier: 0000-0002-0824-0207
authors.initials: CJ
authors.lastname: Lee
authors.affiliation: The Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
authors.forename: S N
authors.initials: SN
authors.lastname: Bleich
authors.affiliation: The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: R R
authors.initials: RR
authors.lastname: Kalyani
authors.affiliation: The Johns Hopkins University School of Medicine, Baltimore, MD, USA.|The Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.|The Welch Center for Prevention, Epidemiology, Prevention, and Clinical Research, Baltimore, MD, USA.
authors.forename: J M
authors.initials: JM
authors.lastname: Clark
authors.affiliation: The Johns Hopkins University School of Medicine, Baltimore, MD, USA.|The Welch Center for Prevention, Epidemiology, Prevention, and Clinical Research, Baltimore, MD, USA.
authors.forename: K A
authors.initials: KA
authors.lastname: Gudzune
mesh_terms: D001786:Blood Glucose / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D004038:Diet, Reducing; D015444:Exercise; D006801:Humans; D009765:Obesity / Q000097:blood / Q000628:therapy*; D050177:Overweight / Q000097:blood / Q000628:therapy*; D016032:Randomized Controlled Trials as Topic; D018570:Risk Assessment; D016896:Treatment Outcome; D061217:Weight Reduction Programs
chemical_list: D001786:Blood Glucose
keywords: Commercial weight loss; glucose; haemoglobin A1c; type 2 diabetes mellitus