Effectiveness of a Low-Carbohydrate Diet on Glycemic Control in Patients with Type 2 Diabetes: A Randomized Controlled Trial

Abstract

Background: Type 2 diabetes mellitus (T2DM) is a growing public health concern in Thailand. Effective glycemic control is essential to prevent complications. A low-carbohydrate diet (LCD) may help improve blood glucose and lipid levels.
Objective: To evaluate the effectiveness of a low-carbohydrate diet on glycemic control, lipid profile, and renal function among patients with T2DM.
Methods: This study was a randomized controlled trial with a total of 112 participants, divided into an intervention group and a control group (56 patients each). The intervention group received counseling on low-carbohydrate diet consumption (<130 g/day) for 24 weeks, while the control group received standard diabetes education.
Results: After 24 weeks, HbA1c decreased from 7.4±0.95% to 7.0±1.15% (p=0.02), triglycerides decreased from 143.9±70.56 to 123.3±75.97 mg/dL (p<0.01), and total cholesterol decreased from 172.3±37.26 to 163.9±26.40 mg/dL (p<0.01) in the intervention group. The proportion of patients achieving HbA1c <6.5% increased from 19.6% to 41.1% in the LCD group, while no change was observed in the control group. However, when adjusted by ANCOVA and logistic regression accounting for duration of diabetes, no statistically significant differences were found in any variables.
Conclusion: A low-carbohydrate diet may promote glycemic and triglyceride control in patients with type 2 diabetes mellitus within the intervention group without adverse effects on renal function. Nevertheless, when adjusted for diabetes duration, no statistically significant differences between groups were observed.