A food-based, low-energy, low-carbohydrate diet for people with type 2 diabetes in primary care: A randomized controlled feasibility trial.

Aim: To examine the feasibility of a food-based, low-energy, low-carbohydrate diet with behavioural support delivered by practice nurses for patients with type 2 diabetes.

Materials And Methods: People with type 2 diabetes and a body mass index (BMI) of ≥30 kg/m were randomized 2:1 to intervention or control (usual care) and assessed at 12 weeks. The intervention comprised an 800-1000 kcal/day, food-based, low-carbohydrate (<26% energy) diet for 8 weeks, followed by a 4-week weight maintenance period and four 15-20-minute appointments with a nurse. Primary outcomes were feasibility of recruitment, fidelity of intervention delivery and retention of participants at 12 weeks. Secondary outcomes included change in weight and HbA1c. Focus groups explored the intervention experience.

Results: Forty-eight people were screened, 33 enrolled and 32 followed-up. Mean (±SD) weight loss in the intervention group was 9.5 kg (± 5.4 kg) compared with 2 kg (± 2.5 kg) in the control group (adjusted difference - 7.5 kg [-11.0 to -4.0, P < 0.001]). Mean reduction in HbA1c in the intervention group was 16.3 mmol/mol (± 13.3 mmol/mol) compared with 0.7 mmol/mol (±4.5 mmol/mol) in the control group (difference - 15.7 mmol/mol [-24.1 to -7.3, P < 0.001]).

Conclusions: It is feasible to recruit participants to a food-based, low-energy, low-carbohydrate intervention, for practice nurses to deliver the programme in primary care, and to retain participants in both groups. There is evidence of clinically significant short-term improvements in weight and glycaemic control.