A fresh start with high hopes: a qualitative evaluation of experiences of the Total Diet Replacement phase of the NHS Low Calorie Diet Programme pilot

Background: The National Health Service (NHS) Low Calorie Diet (LCD) programme in England aims to support people with type 2 diabetes (T2DM) to lose weight, improve glycaemic parameters and potentially achieve diabetes remission. The programme pilot launched in 2020 using three different delivery models: one-to-one, group and digital via an App. Service users begin the programme with 12 weeks of Total Diet Replacement (TDR). This study aims to understand the experience of this TDR phase from the service user perspective. Methods: This was a co-produced qualitative longitudinal and cross-sectional study, underpinned by a realist informed approach using semi-structured interviews and photovoice techniques. Service users (n=45) from the NHS LCD programme were recruited across the three delivery models and 21 pilot sites in England. Data were analysed using a thematic approach. Results: Participant demographics were representative of the overall LCD pilot population sample and included experiences from a mix of delivery models and providers. Three themes were presented chronologically. 1) life pre-LCD: the LCD programme was viewed as an opportunity to reset eating behaviours and improve quality of life; 2) experience of TDR: flexibility in allowing supplementary non-starchy vegetables and adapting the flavour and texture of TDR products supported adherence; 3) looking ahead to food reintroduction: at the end of the TDR phase, weight and glycaemia had reduced, while subjective energy levels and mobility improved. Some participants were concerned about progressing to the food reintroduction phase and the possibility of weight regain. Conclusions: The paper reports insight from the TDR phase of the LCD programme. The co-production of this work has resulted in several recommendations for policy and practice which have informed the national roll out of the programme.