Effect of a behavioral/nutritional intervention program on weight loss in obese adults: a randomized controlled trial

Health professionals are in need of more information about the weight-loss outcomes of using commercial weight-loss programs.

A commercial behavioral intervention program using meal replacements, fruits, and vegetables (MR-FV) was compared with usual-care weight-loss counseling.

Obese volunteers were randomly allocated to usual-care weight-loss counseling or participation in an MR-FV standardized behavioral education program. The MR-FV group attended weekly weight-loss classes for 16 weeks and weekly maintenance classes for 8 weeks.

Obese women or men aged 20 to 65 years were recruited from the community through a commercial program provided at a university medical center.

The control group (C group) received weight-management counseling from an experienced dietitian, while the intervention group (MR-FV group) participated in scheduled behavioral weight-loss classes. The MR-FV group participants were encouraged to consume 3 shakes, 2 entrées, and 5 servings of fruits or vegetables daily, and achieve physical activity goals (expend ≥ 8.4 mJ/week); they kept records and placed midweek phone calls. The C group was counseled at baseline, 8 weeks, and 16 weeks.

Both groups were seen at baseline, and 8, 16, and 24 weeks for assessment of weight, risk factors, and side effects.

The primary data analysis was intention to treat.

Thirteen of 16 subjects (81.3%) in the C group and 18 of 22 subjects (81.8%) in the MR-FV group completed the 24-week study. Mean weight losses for the C group were: 1.3% (standard error [SE], 0.9) at 8 weeks; 0.7% (SE, 1.1) at 16 weeks; and 0.7% (SE, 1.1) or 0.7 kg at 24 weeks. Mean weight losses for the MR-FV group were: 8.5% (SE, 0.6) at 8 weeks, 12.5% (SE, 0.9) at 16 weeks, and 13.9% (SE, 1.1) or 13.7 kg at 24 weeks.

A behavioral intervention with a low-energy diet including 5 meal replacements and 5 servings of fruits or vegetables enabled obese individuals to lose 13 kg more than control subjects over a 24-week period.