The effect of the 7-day high-salt (HS) diet without (HS group) and with vitamin C and E (HS+C+E group) supplementation on hydrogen peroxide and peroxynitrite (DCF-DA) formation in peripheral blood leukocytes (PBL)—granulocytes, monocytes, and lymphocytes in young healthy individuals. (A) shows gating strategy for excluding doublets and defining leukocytes subpopulations based on the size (FSC) and complexity (SSC), (B) shows histograms expressing the level of oxidative stress in individual leukocyte populations, and (C) shows the comparison of the expression of oxidative stress in monocytes at study enrollment (gray), after 7 days of low-salt (blue) and after 7 days of high-salt diets (red). (D) shows median fluorescence intensity of DCF-DA FITC. (D,E) shows the median fluorescence intensity of DCF-DA FITC on PBLs in HS and HS+C+E groups. Data are presented as mean ± SD. * p < 0.05, LS diet vs. HS diet within the HS group.