Effectiveness of Internet‐Delivered Cognitive Behavioural Therapy (ICBT) in Improving Weight‐Loss and Psychosocial Well‐Being Among Adults With High BMI: A Systematic Review

ABSTRACT

Aim

To examine the effectiveness of Internet-delivered Cognitive Behaviour Therapy (ICBT) in improving psychosocial well-being and promoting weight-loss in adults ≥ 18 years with BMI ≥ 25 kg/m².

Background

Global obesity engenders significant physical and psychosocial health consequences. Second-wave ICBT focused on restructuring negative thoughts and behaviours has been explored as a potential intervention for elevated BMI and mental health concerns, but its effectiveness remains to be fully established, making further evaluation essential.

Methods and Data Sources

Eight databases were searched from inception to January 2025 for randomised controlled trials (RCTs), including participants ≥ 18 years with BMI ≥ 25 kg/m² and second-wave ICBT evaluating BMI, weight, depression, eating behaviours, and self-esteem. This review followed PRISMA 2020. Study quality was assessed using the Cochrane Risk of Bias (ROB 2) and GRADE. Data were extracted using a modified Cochrane form. Random-effects meta-analysis calculated Standardised Mean Differences (SMD) with 95% confidence intervals, with subgroup analyses exploring heterogeneity.

Results

Nine trials with 2278 participants were included. Significant improvements were seen in BMI, weight, and depressive symptoms while self-esteem effects were small and non-significant. Compared with passive controls, ICBT showed greater improvements in BMI and weight, whereas differences versus active control were smaller and inconsistent. Face-to-face CBT demonstrated superior outcomes for depression and self-esteem. Male-tailored interventions showed greater improvements. Shorter programmes yielded larger short-term weight loss, while longer programmes supported more sustained effects. Narrative synthesis indicated improvements in emotional and external eating, with increased mindful and restrictive eating behaviours.

Conclusion

ICBT improved weight, BMI, and depressive symptoms, with limited evidence for self-esteem. Male-tailored interventions and longer programmes may enhance sustainable outcomes.

Impact

Future ICBT programs should integrate strategies targeting sustainable weight loss and psychosocial well-being to support long-term outcomes.

No Patient or Public Contribution

Patients or members of the public were not involved, as this study synthesised previously published data.

Trial Registration

PROSPERO registration number: CRD42024497961