Inclusion Criteria:  Group 1: patients with ileocolic Crohn's disease requiring surgery Group 2: Patients requiring ileal and / or colonic surgery for a reason other than Crohn's disease or ulcerative colitis (for example, cancer, polyp or diverticulum).  Exclusion Criteria:  Vegetarian or vegan patients, celiac disease, gluten sensitivity, eating disorders, people with a particular diet or eating behavior or suffering from obesity or anorexia Surgical history: patient having undergone intestinal resection Current treatments: patient receiving antibiotic or probiotic treatment within 6 weeks prior to inclusion / patient having taken topical treatment (suppositories or enema of 5ASA or corticosteroids) within 6 weeks prior to inclusion