 The main purposes of this study are: a to explore whether the gut microbiota changes we observed in this previous study in children with CD during EEN are disease specific or not, and b to develop a novel food-based diet Crohns Disease TReatment-with-EATingCD-TREAT diet which will induce changes to the metabolic activity and bacterial composition of the gut microbiota of healthy people, similar to those seen on EEN, the first-line treatment for active paediatric CD. 