JMIR Publications

ABSTRACT

Background:

Approximately one-third of university students are overweight or obese, and a similar proportion experience anxiety or depression. Despite the interrelated nature of weight and mental health, interventions rarely address these issues simultaneously in young adults. Digital peer support interventions have the potential to promote healthy lifestyles and mental well-being. However, evidence is limited on whether a digital peer-driven approach can concurrently improve weight management and mental health in pre-obese university populations.

Objective:

This randomized controlled trial (RCT) aimed to evaluate the efficacy of a digital peer support program in concurrently improving weight management and mental health outcomes among pre-obese university students.

Methods:

In a single blind parallel group RCT, 216 pre obese students were allocated equally among three six months arms, which were a peer support intervention, an active wellness control and a wait list control. The peer support arm began with an interactive online workshop followed by moderated WeChat group discussions, daily micro tasks, biweekly group challenges and digital badges to reinforce engagement. The active control group received the same schedule and formats but focused on general wellness topics. The wait list group completed the same assessments without any intervention during the study period. The primary outcome measured change in body mass index (BMI) from baseline to six months. Secondary outcomes included weekly physical activity measured in MET minutes, self-esteem, loneliness, anxiety and depression, all assessed with validated instruments at baseline and at two, four and six months. Analyses adhered to the intention to treat principle and employed linear mixed effects models to examine the interaction between group and time.

Results:

Follow-up rates exceeded 90% at each assessment and baseline characteristics were balanced. At six months the peer-support group achieved a greater BMI reduction than the active control by 0.47 kg/m² (95% CI −0.89 to −0.04) and wait-list by 0.54 kg/m² (95% CI −0.85 to −0.01). Weekly MET-minutes were 129.5 higher than active control (95% CI 53.3 to 205.6) and 152.9 higher than wait-list (95% CI 68.4 to 237.4). Self-esteem increased by 1.81 points versus active control (95% CI 0.22 to 3.39) and 1.99 points versus wait-list (95% CI 0.21 to 3.76). Loneliness scores fell by 3.79 points relative to active control (95% CI −7.03 to −0.56) and by 5.02 points relative to wait-list (95% CI −8.38 to −1.66). No significant differences emerged for anxiety or depression.

Conclusions:

A comprehensive digital peer-support program delivered via WeChat produced modest but clinically meaningful improvements in weight management, physical activity, self-esteem and social connectedness among pre-obese undergraduates compared with both an attention-matched wellness program and no intervention. These findings suggest that integrating peer support into scalable digital platforms can simultaneously address physical and psychosocial health in at-risk university populations. Clinical Trial: ClinicalTrials.gov NCT06966661