A randomized controlled trial of a weight loss maintenance program in adults with obesity: the WLM3P study

Background/objectives: The escalating obesity epidemic necessitates effective, sustainable weight loss (WL) and maintenance strategies. This study aimed to evaluate the effectiveness of the Weight Loss Maintenance 3 Phases Program (WLM3P) in achieving a clinically significant long-term weight loss (WL) (>= 5% initial WL at 18 months) in adults with obesity compared to a standard low-carbohydrate diet (LCD). Subjects/methods: In this two-phase trial, 112 participants targeting initial WL (0-6 months) and subsequent maintenance (7-18 months) were randomly assigned to either WLM3P or LCD groups. Outcomes assessed included change in body weight (kg, %), improvements in body composition, and metabolic profile. Results: Of 112 randomized participants, 69% (n = 77) completed the study. At 18 months, WL in the WLM3P group (n = 40) was 15.5 +/- 8.3% compared to 9.6 +/- 8.5% in the LCD group (n = 37) (p < 0.001). The odds ratio of achieving WL >= 10% and >= 15% were significantly higher in the WLM3P group. Complete-case analysis revealed significantly greater improvements in BMI, body fat mass, visceral fat area, waist circumference, waist-to-hip ratio, HDL, and triglyceride/HDL ratio in WLM3P than in LCD. No serious adverse events were reported. Conclusion: Both programs effectively promoted clinically relevant WL and its maintenance. However, the WLM3P program was more successful in helping participants achieve greater WL targets of >= 10% and >= 15%, along with other clinical benefits, after an 18-month intervention.