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.
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.
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.
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.
Registered clinical trial: This study was registered on 10 February 2015 through the Australian New Zealand Clinical Trials Registry (ANZCTR). The allocated Australian Clinical Trial Registry Number (ACTRN) is: ACTRN12615000114549.
We thank our wonderful research assistant Ms. Simӧna Sterling for conducting our anthropometric measurements. We also thank Professor Ben Fletcher for his involvement and support with the psychometric measures. Finally, we gratefully acknowledge the 75 individuals who participated in this study.Funding
GC was supported by an Australian Government Research Training Program Scholarship. RT and EB are supported by NHMRC grants (APP1104136, APP1044904). PG is supported by an NHMRC Australian Fellowship grant (GNT1080042). EI received no funding with respect to this study.Author contributions
GC had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Study concept and design: GC, PG. Acquisition of data: GC. Analysis and interpretation of data: GC, RT, EB. Drafting of the manuscript: GC, PG, RT, EI. Critical revision of the manuscript for important intellectual content: GC, RT, EB, EI, PG. Statistical analysis: GC, RT, EB.