The IBS patients showed significantly lower IL‐10 serum levels than controls, 178.04 ± 143.65 vs. 383.34 ± 163.82 pg/μL (p < 0.01) (Figure 2A) and lower IL‐4: 286.86 ± 39.80 vs. 927.75 ± 298.08 pg/μL (p < 0.01) (Figure 2B). This evidence concerns the gene IL4 and irritable bowel syndrome.