# Efficacy of a low‐carbohydrate diet combined with exercise on glycemic control and metabolic health in type 2 diabetes mellitus: A systematic review and meta‐analysis

## TL;DR

This study finds that combining a low-carb diet with exercise does not significantly improve blood sugar control in type 2 diabetes compared to other diets with exercise.

## Contribution

The novel contribution is a systematic review and meta-analysis comparing low-carb diets with exercise to other diets with exercise in type 2 diabetes.

## Key findings

- No significant differences in glycemic control or body composition between low-carb and non-carb-restricted diets with exercise.
- Lipid profiles slightly improved with low-carb diets, especially in shorter interventions.
- Future research should explore differences among types of low-carb diets for tailored recommendations.

## Abstract

This study aims to evaluate the efficacy of a low‐carbohydrate diet with exercise (LCD + EX) compared to a non‐carbohydrate‐restricted diet with exercise (NRD + EX) on glycemic control and other clinically relevant metabolic health outcomes in adults with type 2 diabetes mellitus (T2DM).

A systematic search was conducted across five databases from inception to August 1, 2025. Randomized controlled trials (RCTs) were analysed using random‐effects models, with outcomes expressed as mean difference (MD) and 95% confidence intervals (CIs).

Twelve RCTs involving 805 participants were included. No significant differences were observed between LCD + EX and NRD + EX in the overall analysis for glycosylated haemoglobin (MD [95% CI]: −0.18 [−0.43, 0.07] %, p = 0.16), fasting glucose (−0.30 [−0.67, 0.07] mmol/L, p = 0.11), insulin levels (−1.45 [−3.62, 0.73] μIU/mL, p = 0.19), and HOMA‐IR (−0.17 [−0.46, 0.11] arbitrary unit, p = 0.23). Additionally, no between‐group differences were observed for body composition, blood pressure, total cholesterol, and low‐density lipoprotein cholesterol levels. However, changes in high‐density lipoprotein cholesterol and triglyceride levels favoured the LCD + EX group. Subgroup analysis for intervention duration ≤6 months revealed a trend of improvement for HbA1c (−0.30 [−0.57, −0.03] %, p = 0.03) and fasting glucose (−0.34 [−0.69, 0.00] mmol/L, p = 0.05) in the LCD + EX group.

LCD + EX did not demonstrate significant overall improvements in glycemic control or body composition compared to NRD + EX in adults with T2DM. However, potential benefits were noted in lipid profiles and in shorter interventions. Future studies can focus on differences in metabolic outcomes among various types of LCD, enabling tailored clinical recommendations.