One of the primary underlying mechanisms is the circulating cytokines released from the systemic inflammatory response (i.e., interleukin 6, interleukin 1β, and tumor necrosis factors), triggering mechanisms that contribute to the pathogenesis of malnutrition, including brain circuits disorder, protein degradation, and neuroendocrine disturbance, ultimately causing disease-related anorexia, sarcopenia, cognitive decline, and frailty [11, 12, 26, 27]. Here, IL6 is linked to nutritional deficiency disease.