The Effect of Vitamin C Supplementation on Serum Lipids in Type II Diabetics

Introduction: The pathogenesis of diabetic disorders are unknown and may be multifactorial. One of the most important mechanisms of complications is glycosilation of proteins such as haemoglobin. Structurally, Vitamin C is similar to glucose and can act as glucose in many chemical reactions, therefore it may prevent non- enzymatic glycosilation of proteins such as haemoglobin and lipoproteins. Previous studies showed that vitamin C supplementation could improve dyslipidemia. Because of the availability and safety of vitamin C supplementation this study was decided to find out the effect of vitamin C on serum lipid profiles in type II diabetics.

Materials and Methods: 45 diabetic patients who referred to Yazd Diabetes Research Centre (YDRC) were randomly selected for interventional study. A questionnaire was completed for each patient regarding demographic data, type of treatment and duration of the diabetes. Blood sample was collected after an over night fasting of 12 hours lipid profiles; total cholesterol  (Chol), HDL, LDL and triglyceride (TG) were measured.1000 mg of vitamin C was orally administrated for 30 days without any change in the method of treating diabetes to each patient. Measurement of laboratory tests was repeated after 30 days. Paired t-test was used to compare the results.

Results: 22 females (48.9%) and 23 males (51.1%) were studied. The mean age of the patient was 50.6±10.25 years and the mean duration of diabetes was 7.5±5.7 years. There was statistically significant decreasing effect of vitamin C supplementation on total Chol  (P=0.02) and LDL-C (P=0.001). Vitamin C supplementation had a statistically
significant increased level of HDL-C  (P = 0.017) in these patients but there was no statistically significant correlation between vitamin C supplementation and decrease of TG (P=0.85).

Conclusion:  Decreasing LDL and increasing HDL can be due to the effect of vitamin C supplementation on their metabolism in the liver. Therefore vitamin C supplementation has beneficial effects upon lipid metabolism in non-insulin dependent (type II) diabetic patients.