School of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
Department of Global Public Health/Media, Culture, and Communication, Steinhardt School of Culture, Education, and Human Development, New York University, New York, NY 10016, USA.
Nutrients. 2023 Jul 15;15(14):3156. doi: 10.3390/nu15143156.
Dietary patterns play a critical role in diabetes management, while the best dietary pattern for Type 2 diabetes (T2DM) patients is still unclear. The aim of this network meta-analysis was to compare the impacts of various dietary approaches on the glycemic control of T2DM patients.
Relevant studies were retrieved from PubMed, Embase, Web of Knowledge, Cochrane Central Register of Controlled Trials (CENTRAL), and other additional records (1949 to 31 July 2022). Eligible RCTs were those comparing different dietary approaches against each other or a control diet in individuals with T2DM for at least 6 months. We assessed the risk of bias of included studies with the Cochrane risk of bias tool and confidence of estimates with the Grading of Recommendations Assessment, Development, and Evaluation approach for network meta-analyses. In order to determine the pooled effect of each dietary approach relative to each other, we performed a network meta-analysis (NMA) for interventions for both HbA1c and fasting glucose, which enabled us to estimate the relative intervention effects by combing both direct and indirect trial evidence.
Forty-two RCTs comprising 4809 patients with T2DM were included in the NMA, comparing 10 dietary approaches (low-carbohydrate, moderate-carbohydrate, ketogenic, low-fat, high-protein, Mediterranean, Vegetarian/Vegan, low glycemic index, recommended, and control diets). In total, 83.3% of the studies were at a lower risk of bias or had some concerns. Findings of the NMA revealed that the ketogenic, low-carbohydrate, and low-fat diets were significantly effective in reducing HbA1c (viz., -0.73 (-1.19, -0.28), -0.69 (-1.32, -0.06), and -1.82 (-2.93, -0.71)), while moderate-carbohydrate, low glycemic index, Mediterranean, high-protein, and low-fat diets were significantly effective in reducing fasting glucose (viz., -1.30 (-1.92, -0.67), -1.26 (-2.26, -0.27), -0.95 (-1.51, -0.38), -0.89 (-1.60, -0.18) and -0.75 (-1.24, -0.27)) compared to a control diet. The clustered ranking plot for combined outcomes indicated the ketogenic, Mediterranean, moderate-carbohydrate, and low glycemic index diets had promising effects for controlling HbA1c and fasting glucose. The univariate meta-regressions showed that the mean reductions of HbA1c and fasting glucose were only significantly related to the mean weight change of the subjects.
For glycemic control in T2DM patients, the ketogenic diet, Mediterranean diet, moderate-carbohydrate diet, and low glycemic index diet were effective options. Although this study found the ketogenic diet superior, further high-quality and long-term studies are needed to strengthen its credibility.
饮食模式在糖尿病管理中起着关键作用，而对于 2 型糖尿病（T2DM）患者来说，最佳的饮食模式仍不清楚。本网络荟萃分析的目的是比较各种饮食方法对 T2DM 患者血糖控制的影响。
从 PubMed、Embase、Web of Knowledge、Cochrane 对照试验中心注册库（CENTRAL）和其他额外记录（1949 年至 2022 年 7 月 31 日）中检索相关研究。符合条件的 RCT 是指比较不同饮食方法之间或 T2DM 患者与对照饮食之间至少 6 个月的 RCT。我们使用 Cochrane 偏倚风险工具评估纳入研究的偏倚风险，并使用网络荟萃分析的 Grading of Recommendations Assessment, Development, and Evaluation 方法评估估计的置信度。为了确定每种饮食方法相对于其他方法的综合效果，我们对 HbA1c 和空腹血糖的干预措施进行了网络荟萃分析（NMA），这使我们能够通过结合直接和间接试验证据来估计相对干预效果。
共有 42 项 RCT 纳入了 4809 例 T2DM 患者，比较了 10 种饮食方法（低碳水化合物、中碳水化合物、生酮、低脂、高蛋白、地中海、素食/纯素、低升糖指数、推荐和对照饮食）。共有 83.3%的研究存在低偏倚风险或存在一些关注问题。NMA 的结果表明，生酮、低碳水化合物和低脂饮食在降低 HbA1c 方面显著有效（分别为-0.73（-1.19，-0.28）、-0.69（-1.32，-0.06）和-1.82（-2.93，-0.71）），而中碳水化合物、低升糖指数、地中海、高蛋白和低脂饮食在降低空腹血糖方面显著有效（分别为-1.30（-1.92，-0.67）、-1.26（-2.26，-0.27）、-0.95（-1.51，-0.38）、-0.89（-1.60，-0.18）和-0.75（-1.24，-0.27））与对照饮食相比。综合结果的聚类排名图表明，生酮、地中海、中碳水化合物和低升糖指数饮食在控制 HbA1c 和空腹血糖方面具有良好的效果。单变量荟萃回归显示，HbA1c 和空腹血糖的平均降低仅与受试者的平均体重变化显著相关。
对于 T2DM 患者的血糖控制，生酮饮食、地中海饮食、中碳水化合物饮食和低升糖指数饮食是有效的选择。尽管本研究发现生酮饮食更优，但仍需要更多高质量和长期的研究来增强其可信度。
