Overall , vitamin C did not modify glucose , HbA1c and insulin concentrations .
Meta-regression analyses showed that age was a modifier of the effect of vitamin C on insulin concentration .
Furthermore , the effect size was associated with baseline BMI and plasma glucose levels , and with the duration of the intervention .
In conclusion , greater reduction in glucose concentrations observed in patients with diabetes , older individuals and with more prolonged supplementation .
R and omised controlled trials ( RCTs ) have observed contrasting results on the effects of vitamin C on circulating biomarkers of glycaemic and insulin regulation .
Vitamin C may have similar beneficial effects to Gemfibrozil on serum high-density lipoprotein-cholesterol in type 2 diabetic patients
Objective : Type 2 diabetes mellitus ( DM-T2 ) is commonly associated with increased triglycerides ( TG ) , low-density lipoprotein cholesterol ( LDL-C ) and low high-density lipoprotein cholesterol ( HDL-C ) levels . Fibrates like gemfibrozil are frequently used in diabetic patients to decrease TG and increase HDL-C levels . We compared the efficacy of Vitamin C , an antioxidant vitamin , with gemfibrozil on serum HDL-C in diabetic patients . Methods : Type 2 diabetic patients , referred to our out-patient clinic were r and omly divided into three groups . After 1 month of lifestyle and diet modifications , groups A , B , and C were prescribed 1000 mg Vitamin C , 600 mg gemfibrozil and combination of both , respectively . Before the study initiation and after 6th week of drug prescription , the blood sample s were taken and analyzed for total cholesterol ( Total-C ) , HDL-C , TG , fasting blood sugar ( FBS ) , and hemoglobin A1c ( HbA1c ) levels . Findings : Sixty-seven patients entered , and 50 patients ( 18 male , 32 female ) finished the study . Overall , serum HDL-C increased significantly from 39.8 to 45.2 mg/dL in the participants ( P = 0.001 ) . HDL-C increased 6.3 , 4.4 and 5.0 mg/dL in groups A , B and C , respectively ( related significance s were 0.017 , 0.022 and 0.033 , respectively ) . Significant decrease of serum TG and Total-C occurred in gemfibrozil and combination groups , but not in Vitamin C group . Changes in serum HDL-C between three groups were not significant ( P = 0.963 ) . We found a significant decrease in TG and Total-C in the groups B and C ( P < 0.05 ) , but no significant changes of TG , Total-C , LDL-C , FBS and HbA1c in group A ( P > 0.05 ) . Conclusion : The results demonstrated that Vitamin C may have beneficial effects on HDL-C in diabetic patients without significant effects on plasma glucose or other lipid parameters ; however , its role for the treatment of low HDL-C patients should be evaluated in larger studies
Overall , vitamin C did not modify glucose , HbA1c and insulin concentrations .
Meta-regression analyses showed that age was a modifier of the effect of vitamin C on insulin concentration .
Furthermore , the effect size was associated with baseline BMI and plasma glucose levels , and with the duration of the intervention .
In conclusion , greater reduction in glucose concentrations observed in patients with diabetes , older individuals and with more prolonged supplementation .
R and omised controlled trials ( RCTs ) have observed contrasting results on the effects of vitamin C on circulating biomarkers of glycaemic and insulin regulation .