Randomized controlled trial of a novel lifestyle intervention used with or without meal replacements in work sites.

Abstract

Lifestyle interventions have had limited effectiveness in work sites when evaluated in randomized trials. This study assessed the effectiveness of a novel lifestyle intervention for weight loss (Healthy Weight for Living [HWL]) implemented with or without meal replacements (MR) in work sites. HWL used a new behavioral approach emphasizing reducing hunger and building healthy food preferences, and, unlike traditional lifestyle interventions, it did not require calorie counting. Twelve work sites were randomized to an 18-month intervention (n = 8; randomization within work sites to HWL, HWL + MR) or 6-month wait-listed control (n = 4). Participants were employees with overweight or obesity (N = 335; age = 48 [SD 10] years; BMI = 33 [6] kg/m² ; 83% female). HWL was group-delivered in person or by videoconference. The primary outcome was 6-month weight change; secondary outcomes included weight and cardiometabolic risk factors measured at 6, 12, and 18 months in intervention groups. Mean 6-month weight change was -8.8% (95% CI: -11.2% to -6.4%) for enrollees in HWL and -8.0% (-10.4% to -5.5%) for HWL + MR (p < 0.001 for both groups vs. controls), with no difference between interventions (p = 0.40). Clinically meaningful weight loss (≥5%) was maintained at 18 months in both groups (p < 0.001). A new lifestyle intervention approach, deliverable by videoconference with or without MR, supported clinically impactful weight loss in employees.