Regarding this effect of obesity on the risk of MDD, it appears to be mediated by several specific factors since in obese individuals, the more frequent development of MDD could be explained by poor diet, sedentary lifestyle, and accumulation of visceral fat favoring the activation of some deleterious pathophysiological mechanisms (inflammation, insulin/leptin resistance, and hypertension) for the regulation of mood and emotions [49,71]. Here, INS is linked to obesity due to melanocortin 4 receptor deficiency.