Released by macrophages, Interleukin 1 beta (IL-1β) has been, together with TNF-α, one of the most clinically studied cytokines, as well as being also better associated with anorexia, weight loss and sarcopenia than Interleukin 6 (IL-6) [28,29,30,31]. The gene discussed is IL1B; the disease is Anorexia.