Alterations in the intestinal microbiota composition and its metabolites were not only linked to gastrointestinal diseases such as inflammatory bowel disease (IBD) [12, 13] and irritable bowel syndrome (IBS) [14], but also associated with obesity [15, 16], nonalcoholic fatty liver disease (NAFLD) [17], insulin sensitivity [18], type 2 diabetes mellitus (T2DM) [19], cancer [20, 21], cardiovascular risk [22, 23], central nervous system disease [24], and allergic disease [25]. The gene discussed is INS; the disease is irritable bowel syndrome.