Lifestyle intervention reduces body weight and improves cardiometabolic risk factors in worksites

Abstract

Background: Worksites are potentially effective locations for obesity control because they provide opportunities for group intervention and social support. Studies are needed to identify effective interventions in these settings.

Objective: We examined the effects of a multicomponent lifestyle intervention on weight loss and prevention of regain in 4 worksites (2 intervention and 2 control sites).

Design: Overweight and obese employees (n = 133) enrolled in this pilot worksite-randomized controlled trial with a 0-6-mo weight-loss phase and a 6-12-mo structured weight-maintenance phase. The intervention combined recommendations to consume a reduced-energy, low-glycemic load, high-fiber diet with behavioral change education. Outcome measurements included changes in body weight and cardiometabolic risk factors.

Results: The mean ± SEM weight loss was substantial in intervention participants, whereas control subjects gained weight (-8.0 ± 0.7 compared with +0.9 ± 0.5 kg, respectively; P < 0.001), and 89% of participants completed the weight-loss phase. Intervention effects were not significant at the 0.05 level but would have been at the 0.10 level (P = 0.08) in a mixed model in which the worksite nested within group was a random factor. There were also significant improvements in cardiometabolic risk factors in intervention compared with control subjects regarding fasting total cholesterol, glucose, systolic blood pressure, and diastolic blood pressure (P ≤ 0.02 for each). No significant weight regain was observed in participants who enrolled in the structured weight-maintenance program (0.5 ± 0.7 kg; P = 0.65), and overweight and obese employees in intervention worksites who were not enrolled in the weight-loss program lost weight compared with subjects in control worksites (-1.3 ± 0.5 compared with +0.7 ± 0.2 kg, respectively; P = 0.02).

Conclusion: Worksites can be effective for achieving clinically important reductions in body weight and improved cardiometabolic risk factors. This trial was registered at clinicaltrials.gov as NCT01470222.

FIGURE 1.

Flow of site and participant recruitment, screening, and assessment.

FIGURE 2.

A: Mean (±SEM) changes in weight for intervention (n = 84) and control (n = 34) groups during the 6-mo weight-loss program and 6-mo structured weight-maintenance program (n = 40). P values were calculated by using the log of the ratio of 6-mo:baseline weight controlled for age, sex, and log-transformed baseline weight. Weights during the structured weight-maintenance (months 6–12) were obtained for a subset of subjects whose weight loss at month 6 was slightly greater than that of the full intervention group. The subset gained 0.5 ± 0.7 kg (P = 0.65) from months 6–12. B: Change in weight from baseline to 6 mo for each subject in intervention (filled bars) and control (open bars) groups.