Moreover, the serum levels of IL-6 (unpaired two-tailed t-test, t14 = 4.311, p = 0.0007) and lipopolysaccharide (LPS) (unpaired two-tailed t-test, t8 = 4.085, p = 0.0035) were significantly higher in the IBS group than in the CON group, whereas the expression level of tumor necrosis factor-α (TNF-α) showed no difference between the two groups (unpaired two-tailed t-test, t14 = 0.4516, p = 0.6585; Figure 1Q–S). Here, IL6 is linked to irritable bowel syndrome.