Strategic Center for Diabetes Research, College of Medicine, King Saud University, Riyadh, Saudi Arabia.
Nutr Rev. 2022 Feb 10;80(3):488-502. doi: 10.1093/nutrit/nuab040.
There is renewed interest in using very low-carbohydrate ketogenic (VLCK) diets to manage diabetes. Many clinical trials have been published, often with mixed results.
This meta-analysis compares the effect of a VLCK diet on glycemic control, body weight, lipid profile, medication use, and dropouts with that of recommended diets for 12 weeks or longer in people with type 2 diabetes.
Ovid MEDLINE, Ovid Embase, CENTRAL, and CINAHL databases were searched (January 1980 through September 2019).
Two authors independently reviewed search results to select randomized controlled trials (RCTs) comparing a VLCK diet (carbohydrate intake < 50 g/d or < 10% of total energy) with any recommended diet for type 2 diabetes in adults. Discrepancies were resolved after consulting with the third author.
Eight RCTs with 648 participants were identified.
Compared with control diets, the VLCK diet resulted in a greater decrease in hemoglobin A1c after 3 months (weighted mean difference[WMD]: -6.7 mmol/mol; 95%CI, -9.0 to -4.4) (WMD: -0.61%; 95%CI, -0.82 to -0.40; P < 0.001; moderate-certainty evidence) and after 6 months (WMD: -6.3 mmol/mol; 95%CI, -9.3 to -3.5) (WMD: -0.58%; 95%CI, -0.85 to -0.32; low-certainty evidence). There was a significantly greater weight loss with the VLCK diet after 3 months (WMD: -2.91 kg; 95%CI, -4.88 to -0.95; low-certainty evidence) and after 6 months (WMD: -2.84 kg; 95%CI, -5.29 to -0.39; low-certainty evidence). The VLCK diet was not better than a control diet after 12 months. It was superior in decreasing triglyceride levels, increasing high-density lipoprotein cholesterol levels, and reducing the use of antidiabetic medications for up to 12 months.
The VLCK diet appears to control glycemia and decrease body weight for up to 6 months in people with obesity and diabetes. Beneficial changes in serum triglycerides and high-density lipoprotein cholesterol, along with reductions in antidiabetic medications, continued in the VLCK group until 12 months. However, the quality of currently available evidence is not sufficient to recommend VLCK diets. A major limitation of the VLCK diet is patients' lack of adherence to carbohydrate restriction.
PROSPERO registration number CRD42020154700.
人们对使用极低碳水化合物生酮（VLCK）饮食来控制糖尿病重新产生了兴趣。已经发表了许多临床试验，但结果往往不一致。
这项荟萃分析比较了 VLCK 饮食与推荐的饮食对 2 型糖尿病患者 12 周或更长时间的血糖控制、体重、血脂谱、药物使用和脱落的影响。
Ovid MEDLINE、Ovid Embase、CENTRAL 和 CINAHL 数据库进行了检索（1980 年 1 月至 2019 年 9 月）。
两名作者独立审查检索结果，以选择比较 VLCK 饮食（碳水化合物摄入量<50g/d 或<总能量的 10%）与任何推荐的 2 型糖尿病成人饮食的随机对照试验（RCT）。在咨询第三位作者后解决了分歧。
确定了 8 项包含 648 名参与者的 RCT。
与对照组相比，VLCK 饮食在 3 个月时血红蛋白 A1c 下降更大（加权均数差[WMD]：-6.7mmol/mol；95%CI，-9.0 至-4.4）（WMD：-0.61%；95%CI，-0.82 至-0.40；P<0.001；中等确定性证据）和 6 个月时（WMD：-6.3mmol/mol；95%CI，-9.3 至-3.5）（WMD：-0.58%；95%CI，-0.85 至-0.32；低确定性证据）。VLCK 饮食在 3 个月时（WMD：-2.91kg；95%CI，-4.88 至-0.95；低确定性证据）和 6 个月时（WMD：-2.84kg；95%CI，-5.29 至-0.39；低确定性证据）体重减轻更明显。VLCK 饮食在 12 个月时并不优于对照组饮食。它在降低甘油三酯水平、增加高密度脂蛋白胆固醇水平和减少糖尿病药物使用方面优于对照组，最长可达 12 个月。
在肥胖和糖尿病患者中，VLCK 饮食似乎可以控制血糖并在 6 个月内减轻体重。在 12 个月时，血清甘油三酯和高密度脂蛋白胆固醇的有益变化以及糖尿病药物的减少仍持续存在于 VLCK 组。然而，目前可用证据的质量不足以推荐 VLCK 饮食。VLCK 饮食的一个主要限制是患者对碳水化合物限制的不遵守。
PROSPERO 注册号 CRD42020154700。
