Meal replacements, reduced energy density eating, and weight loss maintenance in primary care patients: a randomized controlled trial.

ABSTRACT

OBJECTIVE: To compare the presence or absence of meal replacements (MRs) and an energy density (ED) intervention to facilitate weight loss maintenance. DESIGN AND METHODS: A total of 238 overweight primary care patients (mean body mass index = 39.5 kg/m(2) ) began the study; 132 completed the 12-week weight loss phase. Participants were randomly assigned to one of four maintenance conditions formed by crossing the presence or absence of MRs (MR+/MR-) and of the ED program (ED+/ED-) during a subsequent 9-month maintenance phase. Follow-up assessments occurred 1 and 2 years after treatment termination. RESULTS: Participants initially lost 6.1 kg. Analyses of variance based on weight change from the beginning of the maintenance phase to the 2-year follow-up produced a significant interaction. All groups except ED+/MR- regained substantial weight during follow-up; the ED+/MR- group regained significantly less weight than the control group at both follow-up assessments. No significant effects of treatment were found for several variables that were expected to mediate these outcomes. CONCLUSIONS: Because weight losses achieved in lifestyle change programs for obesity are rarely maintained, the superior outcome achieved by the ED+/MR- condition is notable. Nonetheless, methodological issues and inability to identify a potential mediator of this outcome make replication of this finding essential.