Effect of a nutrition education programme on clinical status and dietary behaviours of adults with type 2 diabetes in a resource-limited setting in South Africa: a randomised controlled trial.

Objective: To evaluate the effect of a participant-customised nutrition education programme on glycated Hb (HbA(1c)), blood lipids, blood pressure, BMI and dietary behaviours in patients with type 2 diabetes mellitus.

Design: A randomised controlled trial. The control group (n 41) received education materials. The intervention group (n 41) received the same education materials and participated in eight weekly (2-2·5 h) group nutrition education sessions and follow-up sessions. Outcomes were assessed at 6 and 12 months. An intention-to-treat analysis was conducted. ANCOVA compared the groups (adjustments for baseline values, age, sex and clinic).

Setting: Two community health centres, Moretele sub-district (North West Province), South Africa.

Subjects: Adults (aged 40-70 years) with type 2 diabetes, HbA(1c) ≥8 %.

Results: Differences in HbA(1c) (primary outcome) were -0·64 % (P=0·15) at 6 months and -0·63 % (P=0·16) at 12 months in favour of the intervention group. Starchy-food intake was significantly lower in the intervention group, 9·3 v. 10·8 servings/d (P=0·005) at 6 months and 9·9 v. 11·9 servings/d (P=0·017) at 12 months. Median energy intake was significantly lower in the intervention group at 12 months (5988 v. 6946 kJ/d, P=0·017). No significant group differences in BMI, lipid profile, blood pressure and intakes of macronutrients, vegetables and fruits were observed.

Conclusions: Nutrition education was not efficacious on HbA(1c); however, it improved specific dietary behaviours. Group education and hands-on activities appeared to contribute to the improvement. Optimal goal setting and self-efficacy training/assessment could benefit future nutrition education programmes for people with type 2 diabetes mellitus in resource-limited settings.