AIM 1: We will categorize children ages 7-12 yrs. of age with FGIDs (n=250) as to whether they have/do not have one or more of the following abnormal physiologic changes: a) Autonomic Nervous System imbalance as indicated by low heart rate variability; and/or (b) Abnormalities in gut physiology: Impaired gut barrier function (increased permeability); and/or increased abundance of species of Gammaproteobacteria and/or Clostridia; and/or Gut neuroimmune dysfunction (increased fecal chromogranin A and secretogranin 2 concentrations).
AIM 2: Children will be randomized to the two treatments most commonly used in clinical practice: CBT or a low FODMAP diet for a 3-week treatment period. We will compare the response to the treatments in those with/without abnormal physiologic biomarkers at 3 weeks, 3 months, and 6 months.