Personalized Dietary Interventions and Nutrition Education for Glycemic Management and Health Outcomes in Diabetic Patients Receiving Care at a Nigerian Tertiary Hospital: A Systematic Review

Background: The escalating burden of type 2 diabetes mellitus (T2DM) in Nigeria, characterised by high prevalence, poor glycaemic control, and frequent complications in tertiary hospital settings, highlights the need for effective, context-appropriate interventions. Personalised dietary management combined with structured nutrition education offers a promising approach to improve patient adherence, metabolic outcomes, and quality of life in resource-constrained environments. Aim: To evaluate the effects of personalised dietary management integrated with nutrition education on glycaemic control among adults with T2DM accessing care in Nigerian tertiary hospitals. Methods: This systematic review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and Cochrane recommendations. Comprehensive searches were conducted in PubMed/MEDLINE, Web of Science, CINAHL, and African Journals Online (AJOL). Eleven studies (RCTs and quasi-experimental designs) involving 1,872 adults with T2DM attending Nigerian tertiary hospitals were included. Data extraction focused on intervention details, outcomes, and study characteristics. Risk of bias was assessed using Cochrane RoB 2 for RCTs and the revised JBI tool for quasi-experimental studies. A narrative synthesis of findings was performed. Results: Personalised dietary management with nutrition education produced significant short-term improvements in glycaemic control, with HbA1c reductions of 0.75–2.04% (p < 0.05) and increased achievement of HbA1c targets (<7%). Substantial gains were also observed in self-care practices, dietary knowledge, health-related quality of life (HRQoL via SF-36), weight/BMI reduction, and overall metabolic profiles. Culturally adapted interventions incorporating local foods, portion guidance, food demonstrations, and regular follow-up demonstrated superior and more acceptable outcomes. Benefits were strongest within the first 3–6 months, with some attenuation in longer follow-ups due to adherence and systemic challenges. Conclusion: Personalised dietary management integrated with nutrition education is an effective, feasible strategy for enhancing glycaemic control and broader health outcomes among diabetic patients in Nigerian tertiary hospitals. However, long-term sustainability remains limited by workforce shortages, economic barriers, and inadequate follow-up systems. Scaling these interventions through workforce development, culturally relevant materials, and integrated care protocols is essential to reduce the diabetes burden in Nigeria.