IL-13 is an anti-inflammatory cytokine belonging to the alpha-helix protein family that has been implicated in the pathogenesis of parasitic infection, asthma, and allergic diseases [44], as well as in the metabolic regulation of glucose and insulin resistance [45,46], although clinical findings in humans concerning the role of IL-13 in metabolic diseases are still controversial [46,47]. This evidence concerns the gene IL13 and allergic disease.