The effect of meal frequency and timing on lipid profile, glycemic control, and body composition in individuals with Type 2 Diabetes

Objective: The aim of this study was to evaluate the effects of meal frequency and timing on lipid profile, blood glucose regulation, and body composition in individuals with type 2 diabetes mellitus (T2DM). Method: The study was conducted on 102 individuals diagnosed with T2DM, aged between 18 and 65 years, who applied to the Endocrinology and Metabolic Diseases Outpatient Clinic between March-November 2024. Participants were randomized into one of three dietary models: six meals per day (n=34), three meals per day (n=34), or time-restricted feeding (n=34). Their socio-demographic characteristics and dietary intake records before and after the intervention were collected. Biochemical data were obtained from the hospital system, and anthropometric measurements were taken at 0th, 4th, 8th, and 12th weeks of the study. Results: While a decrease in fasting blood glucose and HbA1c levels was observed in all participants after the intervention (p<0.05), the decrease in the six-meal group was not statistically significant. Triglyceride levels decreased in the six-meal (p=0.013) and time-restricted eating (p<0.001) groups, while total cholesterol decreased only in the time-restricted eating group (p=0.020). Body fat percentage significantly decreased in groups other than the time-restricted group (six meals: 35.2% ± 8.6, 32.4% ± 8.5 (p<0.001), three meals: 40.1% ± 10.3, 37.5% ± 10.4 (p<0.001); time-restricted: 37.6% ± 11.3, 36.2% ± 9.9 (p>0.05)). Energy intake was lower in the time-restricted group after the intervention compared to to the others (p<0.001 for both). Conclusion: Although more significant improvements were observed in the parameters examined in the time-restricted feeding group among the intervention groups, the medications used and the personal preferences of individuals and the guidelines must be taken into account when planning medical nutrition therapies for individuals with T2DM. Key words: type 2 diabetes mellitus, meal frequency, medical nutrition therapy, time-restricted eating, meal time.