Figure 1.

Analysis of selenium biomarkers at baseline. (A) Total selenium concentrations in the serum of omnivores (WD, n = 40), flexitarians (Flex, n = 47), vegetarians (VG, n = 45), and vegans (VN, n = 40) were determined using total reflection X-ray fluorescence spectroscopy (TXRF). The dashed lines indicate the reference range for serum selenium concentrations, with the numbers below the violin plots representing the percentage of subjects below this threshold. (B) Enzymatic activity of glutathione peroxidases (GPX) (WD, n = 38; Flex, n = 47; VG, n = 43; VN, n = 40) was measured by colorimetric assay. The results are shown as violin blot with median and 25- and 75-quartile range (indicated as dotted lines). Diet groups that do not share indices (a,b) differ significantly (Kruskal–Wallis test followed by Benjamini–Hochberg correction (p < 0.05)).