This study will improve our understanding of the mechanisms underlying anorexia in persons with Crohn's disease flare-ups. The practical spin-off from this research is potentially very important for the management of nutritional disorders associated with the disease by guiding diets towards foods that correspond to patients' preferences and/or to modified tastes. In addition, the results could lead to the identification of sensory markers that herald an inflammatory flare-up of the disease.

For patients :

Inclusion Criteria:

• Age between 18 and 60 years,
• Diagnosis of Crohn's disease according to clinical, endoscopic, histological, radiological and biochemical criteria as defined by the European Consensus Conference,
• Men or women who have provided consent and willing to cooperate.

Exclusion Criteria:

• Chronic inflammatory intestinal disease (CIID) other than Crohn's disease: haemorrhagic rectocolitis, undetermined colitis, microscopic colitis.
• Intercurrent disease (diabetes and metabolic disease, liver cirrhosis, progressive cancer, acute or chronic infection, Human Immunodeficiency Virus HIV),
• Organ failure (respiratory, heart, or renal failure, neurological disorders),
• Intolerance to gluten,
• Treatments (other than those used for Crohn's disease) able to interfere with food intake,
• Aversion to foods consumed or smelled,
• Poor understanding of cognitive tasks required.
• Crohn's disease complicated by an abscess or infectious complication
• Acute Crohn's disease defined by a CDAI score > 150

For Controls:

Inclusion Criteria:

• Adult person
• Without follow-up for a chronic pathology
• Having given its consent

Exclusion Criteria:

• Protected adult
• Person not affiliated to a social security system
• Pregnant or breastfeeding woman
• Active smoker
• No one who does not speak French
• Taking treatment that interferes with taste or acts on the central nervous system

understanding of the mechanisms underlying anorexia in persons with Crohn's disease flare-ups