Low-carbohydrate diets in East Asians with type 2 diabetes: A systematic review and meta-analysis of randomized controlled trials.

Aims: Despite the reported success of low-carbohydrate diets in improving glycemic control in the Western countries, no studies have investigated the effects of such diets in Asians. We aimed to conduct a systematic review and meta-analysis of randomized controlled trials to examine the effects of low-carbohydrate diets on glycemic control in East Asian adults.

Materials and methods: We systematically searched the PubMed, Cochrane Library, and Embase databases from inception to June 28, 2023, to identify randomized controlled trials examining the efficacy of low-carbohydrate diets in patients with type 2 diabetes (PROSPERO number CRD 42023453007). The primary outcome was the difference in glycated hemoglobin levels between the low-carbohydrate diet and control groups. The secondary outcome was the difference in body mass index, fasting blood glucose level, blood pressure, and lipid profile.

Results: Six randomized controlled trials met the eligibility criteria. The study duration ranged from 3 to 18 months, with five studies conducted within 6 months. The results showed that low-carbohydrate diets were more beneficial in lowering glycated hemoglobin levels and body mass index than control diets. The risk of bias for the six studies was minimal for two and moderate for four. The heterogeneity among the studies was low.

Conclusions: Low-carbohydrate diets improved glycated hemoglobin levels and body mass index in East Asians compared with control diets. Therefore, carbohydrate restriction may be effective for glycemic management in East Asians with type 2 diabetes for at least 6 months.