CCK and COVID-19: The vistas in the eating behavioral physiology with regard to SARS-CoV-2 infection require more detailed investigations in COVID-19 patients as gustatory and olfactory receptors are also expressed in other tissues such as those in the gut, which is the main site of the release of small peptides (such as cholecystokinin and peptide-YY) that control eating behavior via the vagus nerve [97].