Notably, the increase in tissue and plasma EEC peptide expression was only observed in patients with ileal CD, whereas patients with exclusive colonic CD were found to have a normal ileal expression of EEC peptides and normal postprandial responses to GLP-1 and PYY [116,117], suggesting that disease location may differentially affect postprandial EEC peptide responses to a meal. This evidence concerns the gene GCG and Cowden disease.