Effect of protein and carbohydrate distribution among meals on quality of life, sleep quality, inflammation, and oxidative stress in patients with type 2 diabetes: A single-blinded randomized controlled trial

Background/Objectives Patients with diabetes mellitus have a lower quality of life and sleep compared with healthy individuals. Nutrition therapy has an important role in the management of diabetes and can improve inflammation and quality of life in patients with diabetes. The present study aimed to evaluate the effect of high-protein versus high-carbohydrate intake during evening meal on quality of life, sleep quality, inflammation, and oxidative stress in subjects with type 2 diabetes. Subjects/Methods This is a 10-week randomized controlled trial. 96 adult patients with type 2 diabetes were assigned into one of the following three groups: standard evening meal (ST), high-carbohydrate evening meal (HC), and high-protein evening meal (HP). The effect of these diets was examined on high-sensitivity C-reactive protein, malondialdehyde, quality of life, and sleep quality. Results Sleep quality improved significantly in all groups (p < .05). The quality of life and high-sensitivity C-reactive protein improved in all groups except for the HP group (p < .05). Serum malondialdehyde level did not change significantly throughout the study (p > .05). Conclusions Small manipulation of protein and carbohydrate distribution among the meals might not affect sleep quality. A diet with an even distribution of macronutrients among the meals or with a higher percentage of carbohydrates in the evenings can improve the quality of life and reduce inflammation in patients with type 2 diabetes, while a diet with a higher percentage of protein in the evenings may not improve it.