Comparative Effects of Different Macronutrient Compositions for Type 2 Diabetes Management: A Systematic Review and Network Meta-Analysis of Randomized Trials Publisher Pubmed



Badrooj N¹ ; Jayedi A² ; Shabbidar S¹ Show Affiliations
Source: Journal of Health, Population and Nutrition Published:2025

Abstract

Background: To assess and rank the comparative effects of different exact macronutrient compositions for type 2 diabetes management rather than examining single macronutrients or as a dietary pattern. Methods: PubMed, Scopus, and Cochrane Library Central Register of Controlled Trials were searched. Randomized controlled trials were included. A random-effects network meta-analysis with a Bayesian framework was performed to calculate the mean difference (MD) and 95% credible intervals (CrIs). The certainty of evidence was rated using the GRADE approach. Results: 80 trials with 9232 patients with type 2 diabetes were included in the network meta-analysis. A very low-carbohydrate, high-protein, and calorie-restricted diet had the greatest effect on reducing HbA1c (range of mean difference: − 1.0% to − 1.79%), weight (range of mean difference: -5.83 kg to -10.96 kg), and FPG (range of mean difference: − 2.20 mmol/L to − 2.88 mmol/L) at 6-month follow-up, but at 12-month follow-up, the effect remained only for HbA1c (range of mean difference: − 1.25% to − 1.30%) and FPG (range of mean difference: − 1.21 mmol/L to − 1.27 mmol/L). For weight loss in 12-month follow-up, the low-carbohydrate, high-protein diet was probably the most effective approach (range of mean difference: − 10.05 kg to − 14.52 kg). The best dietary approach to reduce LDL at 6-month follow-up was a low carbohydrate, high protein, calorie-restricted diet (range of mean difference: − 0.49 mmol/L to − 0.59 mmol/L) and at 12-month follow-up, a moderate carbohydrate, standard protein, calorie-restricted diet was effective in reducing LDL (mean difference: − 0.87 mmol/L, 95%CrI − 1.55 to − 0.16). Conclusions: A very low carbohydrate, high protein, calorie-restricted diet can be an effective dietary composition in managing diabetes, but milder dietary carbohydrate restriction for weight loss in the long-term, and improving lipid profiles is needed. © The Author(s) 2025.