Snorgaard Ole, Poulsen Grith M, Andersen Henning K, Astrup Arne
Department of Endocrinology , Copenhagen University Hospital , Hvidovre , Denmark.
Department of Nutrition, Exercise and Sports, SCIENCE , University of Copenhagen , Copenhagen , Denmark.
BMJ Open Diabetes Res Care. 2017 Feb 23;5(1):e000354. doi: 10.1136/bmjdrc-2016-000354. eCollection 2017.
Nutrition therapy is an integral part of self-management education in patients with type 2 diabetes. Carbohydrates with a low glycemic index are recommended, but the ideal amount of carbohydrate in the diet is unclear. We performed a meta-analysis comparing diets containing low to moderate amounts of carbohydrate (LCD) (energy percentage below 45%) to diets containing high amounts of carbohydrate (HCD) in subjects with type 2 diabetes.
We systematically reviewed Cochrane library databases, EMBASE, and MEDLINE in the period 2004-2014 for guidelines, meta-analyses, and randomized trials assessing the outcomes HbA1c, BMI, weight, LDL cholesterol, quality of life (QoL), and attrition.
We identified 10 randomized trials comprising 1376 participants in total. In the first year of intervention, LCD was followed by a 0.34% lower HbA1c (3.7 mmol/mol) compared with HCD (95% CI 0.06 (0.7 mmol/mol), 0.63 (6.9 mmol/mol)). The greater the carbohydrate restriction, the greater the glucose-lowering effect (R=-0.85, p<0.01). At 1 year or later, however, HbA1c was similar in the 2 diet groups. The effect of the 2 types of diet on BMI/body weight, LDL cholesterol, QoL, and attrition rate was similar throughout interventions.
Glucose-lowering medication, the nutrition therapy, the amount of carbohydrate in the diet, glycemic index, fat and protein intake, baseline HbA1c, and adherence to the prescribed diets could all have affected the outcomes.
Low to moderate carbohydrate diets have greater effect on glycemic control in type 2 diabetes compared with high-carbohydrate diets in the first year of intervention. The greater the carbohydrate restriction, the greater glucose lowering, a relationship that has not been demonstrated earlier. Apart from this lowering of HbA1c over the short term, there is no superiority of low-carbohydrate diets in terms of glycemic control, weight, or LDL cholesterol.
营养治疗是2型糖尿病患者自我管理教育的一个组成部分。推荐食用低血糖指数的碳水化合物，但饮食中理想的碳水化合物量尚不清楚。我们进行了一项荟萃分析，比较了2型糖尿病患者中碳水化合物含量低至中等的饮食（LCD，能量百分比低于45%）与碳水化合物含量高的饮食（HCD）。
我们系统回顾了2004年至2014年期间Cochrane图书馆数据库、EMBASE和MEDLINE中评估糖化血红蛋白（HbA1c）、体重指数（BMI）、体重、低密度脂蛋白胆固醇、生活质量（QoL）和损耗率等结局的指南、荟萃分析和随机试验。
我们共纳入10项随机试验，总计1376名参与者。在干预的第一年，与HCD相比，LCD组的HbA1c降低了0.34%（3.7 mmol/mol）（95%可信区间为0.06（0.7 mmol/mol），0.63（6.9 mmol/mol））。碳水化合物限制越大，降糖效果越明显（相关系数R=-0.85，p<0.01）。然而，在1年或更晚时，两组饮食的HbA1c相似。在整个干预过程中，两种饮食对BMI/体重、低密度脂蛋白胆固醇、生活质量和损耗率的影响相似。
降糖药物、营养治疗、饮食中的碳水化合物量、血糖指数、脂肪和蛋白质摄入量、基线HbA1c以及对规定饮食的依从性都可能影响结局。
在干预的第一年，与高碳水化合物饮食相比，低碳水化合物至中等碳水化合物饮食对2型糖尿病患者的血糖控制效果更佳。碳水化合物限制越大，降糖效果越明显，这种关系此前尚未得到证实。除了短期内降低HbA1c外，低碳水化合物饮食在血糖控制、体重或低密度脂蛋白胆固醇方面并无优势。
