Structured diet and physical activity prevent postpartum weight retention

Background: Postpregnancy weight retention contributes to the near-epidemic prevalence of obesity in the United States. This study examines the impact of an individualized, structured diet and physical activity intervention on weight loss in overweight women during the first year postpartum. Methods: Forty overweight postpartum women were randomized to either a structured (STR) or a self-directed (SELF) intervention. Measurements included body weight, percent body fat, daily caloric intake, habitual physical activity, and cardiorespiratory fitness. Subjects in STR received individualized diet and physical activity prescriptions derived from baseline measurements. They met weekly for the first 12 weeks and kept daily food and activity diaries. Subjects in SELF received a single 1-hour educational session about diet and activity. Results: Only 23 of 40 participants remained in the study at 1 year postpartum. Of those, STR (n = 13) had a significant weight loss (7.3 kg, p < 0.01), a significant decrease in percent body fat (6%, p < 0.01), and no change in fat-free mass. SELF (n = 10) had no significant change in weight, percent body fat, or fat-free mass. Conclusions: Women who committed to this one class per week for 12 weeks postpartum had a high likelihood of successful weight loss that persisted at 1 year. Women who were overweight before pregnancy were unlikely to lose the pregnancy-related weight without the help of a formal intervention. This suggests that healthcare professionals should strongly encourage postpartum women to enroll in a structured diet and exercise program.