Effect of vitamin C supplementation on oxidative stress and lipid profiles in hemodialysis patients

Abstract

Background and aims: The increase in oxidative stress is the main factor in acceleration of atherosclerosis, leading to death in hemodialysis patients. Vitamin C is one of the most important antioxidants that inhibits lipid peroxidation and improves endothelial function. This study aims to assess the effects of vitamin C supplementation on lipid profiles as well as markers of lipid peroxidation among hemodialysis patients.

Materials and methods: In this double-blind, randomized, controlled clinical trial, a total of 42 patients were randomly assigned to vitamin C (n=21) or placebo groups (n=21). Patients in the vitamin C group consumed 250 mg vitamin C and those in the placebo group were given placebo every other day for 12 weeks. Fasting blood samples were collected at baseline and at the end of the study to measure serum concentrations of lipid profiles, as well as malondialdehyde (MDA) and vitamin C.

Results: After supplementation with vitamin C, serum vitamin C levels increased significantly in the vitamin C group as compared to baseline (p=0.033). There was also a significant difference in serum vitamin C levels between vitamin C and placebo groups (p=0.001). Serum MDA concentrations were marginally decreased in the vitamin C group after taking supplements (p=0.057). A significant difference was also seen in mean MDA changes between vitamin C and placebo groups (p=0.002). There was a significant difference in serum levels of total cholesterol (p=0.005), low-density lipoprotein (LDL-C) (p=0.012), and LDL-C/high-density lipoprotein (HDL-C) ratio (p=0.018) between the two groups; however, serum triglyceride and HDL-C levels were not significantly different between groups.

Conclusion: Every other day supplementation with 250 mg vitamin C for 12 weeks increases serum vitamin C, decreases MDA levels, and improves lipid profiles in hemodialysis patients.