Health Behaviour Change in Weight Management for People With Higher Weight and Symptoms of Common Mental Health Problems: A Qualitative Study.

Abstract

Background: Adults with higher weight experience disproportionate rates of common mental health problems (CMHPs), including depression, anxiety and post-traumatic stress disorder. Tier 2 Weight Management Services (T2WMS) in the United Kingdom emphasise diet and physical activity with limited psychological input. Evidence on how people with co-occurring CMHPs symptoms experience health behaviour change within these programmes remains limited.

Objective: To explore how adults with higher weight and symptoms of CMHPs engage with health behaviour change in T2WMS, incorporating service user and practitioner perspectives, and to identify barriers, facilitators and service implications.

Design: Qualitative study using semi-structured interviews.

Setting and participants: Service users (n = 11) and healthcare professionals (n = 11) recruited from UK T2WMS.

Main variables studied: Barriers and facilitators to eating behaviours, physical activity, emotion regulation and self-regulation behaviours.

Main outcome measures: Thematic patterns were analysed using codebook thematic analysis within a critical realist frame, with deductive mapping to the COM-B model and Theoretical Domains Framework (TDF).

Results: Five themes captured a dynamic interplay of emotional, social and structural factors: (1) The emotional weight of change, (2) Health on the margins of daily life, (3) Connection and judgement shape the journey, (4) Treating the whole person, and (5) Self-care as a foundation for lifelong change. Barriers to health behaviour change included emotional fluctuation, stigma, low self-efficacy, relational pressures and structural constraints. Facilitators included self-compassion, emotional regulation, small achievable goals, inclusive groups and supportive practitioner relationships.

Discussion and conclusions: Provision centred on weight loss as the primary measure of success, delivered in a standardised format, was poorly aligned with the needs of those with symptoms of CMHPs. Embedding trauma sensitivity, relational safety, flexible pacing and broader outcome measures may better support sustained engagement. Mapping to COM-B/TDF and Behaviour Change Wheel intervention functions offers a psychologically informed framework to guide commissioners and practitioners.

Patient or public contribution: An advisory group of four members (two with lived experience of higher weight and symptoms of CMHPs, two healthcare professionals delivering T2WMS) contributed to study design, recruitment materials and interview guides shaping the study's non-stigmatising terminology. All research participants were also invited to review preliminary findings, which informed refinements to thematic language. Patient and public involvement was documented using the GRIPP2 short-form framework.