Bio-electrical Impedance Analysis in Patients With Functional Dyspepsia

Inclusion Criteria: * Women aged 18 - 75 years * Fulfilling the ROME IV criteria for functional dyspepsia (for FD patients) * FD unexplained by upper GI endoscopy during the past 12 months (mild gastritis allowed) (for FD patients). Exclusion Criteria: * Clinical suspicion of an organic disorder different from FD (patients can be included when this disorder had been excluded); * Abnormality on upper GI endoscopy other than mild gastritis (for FD patients). * Known reflux oesophagitis Los Angeles grade C or D, known Barrett oesophagus, peptic stricture. * H pylori infection, unless treated at least 6 months before; * Known inflammatory bowel disorder; * Known major intestinal motility disorder; * Alcohol (defined as more than 14 U per week) or other substance abuse; * Active psychiatric disorder; * Known systemic or auto-immune disorder with implication for the GI system; * Prior abdominal surgery (with the exception of cholecystectomy or ap-pendectomy); * Any prior diagnosis of cancer other than basocellular carcinoma; * Current chemotherapy; * History of gastro-enteritis in the past 12 weeks; * Dietary supplements unless taken at a stable dose for more than 12 weeks; * Treatment with neuromodulators (one neuromodulator taken at a sta-ble dose for more than 12 weeks is allowed); * Treatment with PPI's during the past 8 weeks * Pregnancy.