GAST and irritable bowel syndrome: This has been supported by the finding that in the stomach and colon of IBS patients, EECs detected by chromogranin A increase toward the values seen in healthy controls following an LFD, probably due to the changes in gastrin-, enterochromaffin-, ghrelin-, and somatostatin-secreting cells in the stomach and enterochromaffin cells and PYY containing L-cells in the colon (79–82).