A randomized clinical trial of beetroot juice consumption on inflammatory markers and oxidative stress in patients with type 2 diabetes

Abstract

Oxidative stress and chronic inflammation are both major underlying factors for the initiation and progression of diabetes, as well as for the development of long-term diabetes-related consequences in patients with type 2 diabetes mellitus (T2DM). This study was designed to evaluate the effects of beetroot juice (BJ) consumption on oxidative stress and inflammatory markers in patients with T2DM. In this trial, 52 patients with T2DM were randomly assigned to either the concentrated BJ or the control group. The BJ group received 12 ml concentrated BJ twice daily, whereas the control group received no intervention. At the baseline and the end of week 12, plasma levels of malondialdehyde (MDA), high sensitive C-reactive protein (hs-CRP), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and nuclear factor-κB (NF-κB) were measured. Compared with the control group, BJ reduced IL-6 (-0.1 vs. 0.83, P = 0.001), TNF-α (-1.28 vs. 5.51, P = 0.001), and NF-κB (-0.03 vs. 0.36, P = 0.005) after 12-week intervention; plasma concentration of MDA and hs-CRP did not change between groups after intervention. Intra-group comparison disclosed that daily BJ consumption could not change oxidative stress and inflammatory markers except for TNF-α (-1.28 ± 2.31, P = 0.026) compared with the baseline. However, the concentrations of IL-6, TNF-α, and NF-κB increased significantly in the control group at the end of week 12 compared to baseline (19.5%, P = 0.001; 120%, P = 0.001; and 69%, P = 0.021, respectively). In conclusion, our study indicates that daily consumption of BJ reduces the concentrations of some inflammatory markers, including IL-6, TNF-α, and NF-κB, which are involved in the pathogenesis of complications of T2DM. PRACTICAL APPLICATION: Beetroot juice concentrate contains nutrients such as antioxidants that can improve the health status of people with type 2 diabetes.