CCK and disorder of glycogen metabolism: The possible explanations for the association between GSD and migraines may be shared risk factors between GSD and migraines, the common peptides such as CCK and CGRP involved in both the pathogenesis of GSD and that of migraines, and multidirectional interaction between GSD and migraine through psychosocial stress [9,10,11,12,13,14,15,16,17,18].