JMIR Publications

ABSTRACT

Background:

By 2035, over half of the global population may be obese, driving significant health and economic burdens. Although lifestyle modification is a preferred approach to weight management, it requires substantial support to be effective.

Objective:

This study aimed to test the effectiveness of a 12-weeks standalone self-regulation weight loss Temporal Self-Regulation Theory (TST)-based app integrating self-regulation, food logging, and dietary nudging in improving weight loss among young adults with excess body weight.

Methods:

A two-arm parallel 1:1 randomized controlled trial was conducted and reported according to the CONSORT-Outcomes 2022 Extension reporting guideline with participants recruited using convenience sampling. Participants completed a face-to-face body composition analysis and online questionnaires on their sociodemographic profile, self-regulation of eating behaviour, overeating habit, time perspective, eating phenotype, nutrition knowledge, and psychological flexibility. Participants in the intervention group joined a 12-weeks app-based program called the eating trigger response inhibition program 2.0 (eTRIP 2.0) while participants in the control group did not receive any active intervention. Both groups were required to return for follow-up measurements at weeks 12 and 24.

Results:

A total of 165 participants were recruited from 14 Nov 2023 to 27 March 2024. The mean body weight differences between the two groups at weeks 0, 12 and 24 were 0.29 kg (95% CI -3.69 kg to 4.28 kg), -1.76 kg (95% CI -5.96 kg to 2.43kg), -1.6 kg (95% CI -5.92 kg to 2.65 kg. A significantly higher improvements of small-to-medium effect sizes with a significant grouptime interactions were observed in the intervention compared to control group at week 12 for weight (-0.89 kg, 95% CI -1.51 kg to -0.27 kg, p=0.005), BMI (-0.32 kg/m2, 95% CI -0.55 kg/m2 to -0.10 kg/m2, p=0.005), waist circumference (-1.50cm, 95% CI -2.80 cm to -0.19cm, p=0.03), waist-hip ratio (-0.01, 95% CI -0.011 to <0.001, p=0.04) and BRI (-0.18, 95% CI -0.34 to -0.02, p=0.02). No significant differences were found in anthropometric change between the two groups from weeks 12 to 24 (when app access was ceased) and from weeks 0 to 24. A slightly higher number of participants preferred to lose weight through physical activity over diet across the 24 weeks.

Conclusions:

This study provides evidence supporting the effectiveness of TST-based app in improving anthropometric outcomes indicative of cardiometabolic risk including weight, BMI, waist circumference, waist-hip ratio and BRI and psychological constructs of depression, perceived health and eating self-regulation. There is potential for scalability in both population and primary health settings. Clinical Trial: Clinicaltrials.gov (NCT05969639)