Effects Of Low-carbohydrate Diet On Body Mass Index And Glucose And Lipid Metabolism In Patients With Type 2 Diabetes Mellitus

Objective:Systematic evaluation the Effects of low-carbohydrate diet on BMI and glucose and lipid metabolism in patients with type 2 diabetes mellitus.Methods:Electronic literature search was performed on PubMed,EMBASE,Cochrane Library,CNKI database for the efficacy of low-carbohydrate diets on glucose and lipid metabolism in patients with type 2 diabetes mellitus since the database establied to October 2018.Use the English keywords "low-carbohydrate diets,carbohydrate-restricted diet,Type 2 Diabetes Mellitus" and the Chinese keywords"low-carbohydrate diet,carbohydrate-restricted diet,type 2 diabetes" as the search terms.Set the inclusion and exclusion criteria,use JADAD scale to evaluate clinical trial methodological quality,collect data and use Revman 5.3 software to statistical analysis.Results:1)14 articles and 989 cases were included in the literature,498 cases in the experimental group and 491 cases in the control group.2)Low-carbohydrate diet can reduced the waist(MD=-2.27,95%CI:-3.91 to-0.63,P=0.007);3)<4 months low carbohydrate diet can reduced BMI(MD=-2.43,95%CI:-3.70 to-1.17,P=0.0002),FPG(MD=-1.68,95%CI:-2.64)?-0.72,P=0.0006),is better than non-low-carbohydrate diet,the difference is statistically significant;But there was no significant difference in BMI(MD=-1.42,95%CI:-4.17 to 1.33,P=0.31)and FPG(MD=-0.94,95%CI:-2.06 to 0.18,P=0.10)between the two groups about>6 months low Carbohydrate diet;4)<4 months(MD=-1.22,95%CI:-2.32 to-0.12,P=0.03)and>12 months(MD=-0.29,95%CI:-0.54 to-0.03,P=0.03)low carbohydrate diet reduced HbAlc is better than non-low-carbohydrate diet,the difference was statistically significant;6-month low-carbohydrate diet reduced HbA1c had no statistical difference between the two groups(MD=-0.76,95%CI:-1.77?0.24,P=0.14);5)? 6 months low carbohydrate diet reduced TG(MD=-0.26,95%CI:-0.40?-0.13,P=0.0002),HDL elevation was not as good as non-low carbohydrate diet(MD=0.20,95%CI:0.14?0.26,P<0.00001);there was no statistical difference between the two groups(MD=0.01,95%CI:-0.08 to 0.09,P=0.91);6)There is no significant difference in European and American races with low-carbohydrate diet and non low-carbohydrate diet on BMI(MD=-0.95,95%CI:-2.69 to 0.79,P=0.29)and FPG(MD=-0.26,95%CI:-0.93)?0.41,P=0.44).Asian races low-carbohydrate diet can reduced BMI(MD=-2.05,95%CI:-3.61?-0.49,P=0.01)and FPG(MD=-1.83,95)%CI:-2.53?-1.14,P<0.00001),is better than non low-carbohydrate diet;7)Asian and European races use LCD and NLCD have similar effects on lipid metabolism indicators,like TG,LDL,HDL;8)low-carbohydrate diet and non low-carbohydrate diet had no effect on systolic blood pressure(MD=1.94,95%CI:-3.50 to 7.39,P=0.48)and diastolic blood pressure(MD=-0.73,95%CI:-1.99 to 0.53,P=0.26).Conclusion:1)The short-term low-carbohydrate diets of the Asian race subgroup can reduce waist circumference and BMI,FPG,but does not show long-term effects.The low-carbohydrate diets has no effect on the BMI and FPG in European and American subgroup;2)The impact of low-carbohydrate diets and non-low-carbohydrate diets on HbA1c does not differ between European,American and Asian races;Compared with non-low-carbohydrate diets,low-carbohydrate diets of less than 4 months and more than 12 months can reduce HbA1c,and there is a statistical difference;3)Long-term low-carbohydrate diets can reduce TG levels in Europeans,Americans and Asians,but HDL is not as high as non-low-carbohydrate diets;The compounds of low-carbohydrate diets and non-low-carbohydrate diets for LDL are equivalent;4)The low-carbohydrate diets has no effect on blood pressure,and there are no racial differences.