Habit-based interventions for weight loss maintenance in adults with overweight and obesity: a randomized controlled trial

OBJECTIVES: The objective of this study was to determine whether habit-based interventions are clinically beneficial in achieving long-term (12-month) weight loss maintenance and explore whether making new habits or breaking old habits is more effective.

METHODS: Volunteer community members aged 18-75 years who had overweight or obesity (BMI ≥ 25 kg/m2) were randomized in a single-blind, three-arm, randomized controlled trial. Ten Top Tips (TTT), Do Something Different (DSD), and the attention-only waitlist (WL) control groups were conducted for 12 weeks from July to October 2015. Participants were followed up post-intervention (all groups) and at 6 and 12-month post-intervention (Ten Top Tips and Do Something Different only). The primary outcome was weight-loss maintenance at 12-month follow-up. Secondary outcomes included weight loss at all time points, fruit and vegetable consumption, exercise, wellbeing, depression, anxiety, habit strength, and openness to change.

RESULTS: Of the 130 participants assessed for eligibility, 75 adults (mean BMI 34.5 kg/m2 [SD 6.2]), with a mean age of 51 years were recruited. Assessments were completed post-intervention by 66/75 (88%) of participants and by 43/50 (86%) at 12 months. At post-intervention, participants in the Ten Top Tips (-3.3 kg; 95% CI -5.2, -1.4) and Do Something Different (-2.9 kg; 95% CI -4.3, -1.4) interventions lost significantly more weight (P = < .001) than those on the waitlist control (-0.4 kg; 95% CI -1.2, 0.3). Both intervention groups continued to lose further weight to the 12-month follow-up; TTT lost an additional -2.4 kg (95% CI -5.1, 0.4) and DSD lost -1.7 kg (95% CI -3.4, -0.1). At 12-month post-intervention, 28/43 (65%) of participants in both intervention groups had reduced their total body weight by ≥5%, a clinically important change.

CONCLUSIONS: Habit-based weight-loss interventions-forming new habits (TTT) and breaking old habits (DSD), resulted in clinically important weight-loss maintenance at 12-month follow-up.