In support of this idea, stress has been shown to alter the gut microbiota by promoting the secretion of neuroendocrine hormones such as corticotropin-releasing hormone, adrenocorticotropin and corticosterone (Guo et al., 2020; Liu et al., 2020), and changes in the gut microbiome have been associated with stress-induced obesity on a high-fat diet and cognitive changes (Wu et al., 2021; Chen et al., 2017; Rao et al., 2021; Xu et al., 2020). Here, CRH is linked to obesity due to melanocortin 4 receptor deficiency.