Evaluation of meal replacements and a home food environment intervention for long-term weight loss: a randomized controlled trial

Am J Clin Nutr. 2018 Jan 1;107(1):12-19. doi: 10.1093/ajcn/nqx005.

Abstract

Background: Lifestyle change treatments for weight loss produce medically meaningful weight reductions, but lost weight is usually regained. Meal replacements (MRs) represent one avenue for improving long-term weight loss. Another, nutrition-focused approach involves having participants make specific changes in the energy density, composition, and structure of the foods in their personal food environments.

Objective: Three conditions were compared: behavior therapy (BT), BT plus MRs (BT+MR), and a nutrition-focused treatment aimed at modifying the home food environment (HFE).

Design: Overweight and obese individuals (n = 262) were randomly assigned to 1 of the 3 conditions. Treatment occurred in weekly groups for 6 mo and in biweekly groups for 6 mo. Assessments were conducted at baseline and at 6, 12, 18, 24, and 36 mo. Multilevel models were used to estimate weight-change trajectories for each participant and to examine the treatment group effect on long-term weight loss.

Results: A multilevel analysis indicated that all 3 groups showed significant weight loss over 12 mo that was gradually regained to the 36-mo follow-up. Mean ± SD percentages of baseline weight loss at 12 mo for BT, BT+MR, and HFE were 9.41% ± 7.92%, 10.37% ± 7.77%, and 10.97% ± 7.79%, respectively. Comparable percentages at 36 mo were 4.21% ± 8.64%, 3.06% ± 6.93%, and 4.49% ± 7.83%. Those in the HFE condition lost more weight than those receiving BT through the 36-mo assessment (P < 0.01), as reflected in 2 treatment × time interactions. Further analyses showed that HFE produced the largest increases in cognitive restraint and that this increase largely mediated the HFE group's improved weight loss.

Conclusion: The nutrition-focused intervention studied here produced modestly greater long-term weight loss than BT, an effect that was largely explainable by an unexpected boost in cognitive restraint in this condition. This study was registered at clinicaltrials.gov as NCT01065974.

Keywords: behavior therapy; diet; home food environment; meal replacements; nutritional intervention; nutritional treatment; obesity; treatment; weight loss.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Body Mass Index
  • Diet
  • Exercise
  • Female
  • Follow-Up Studies
  • Health Behavior
  • Humans
  • Life Style
  • Male
  • Meals*
  • Middle Aged
  • Obesity / therapy*
  • Overweight / therapy*
  • Surveys and Questionnaires
  • Treatment Outcome
  • Weight Loss*
  • Young Adult

Associated data

  • ClinicalTrials.gov/NCT01065974