IPA metabolic interaction network of plasma metabolites having a significant correlation with polyp counts in association with a Genotype by Diet interaction effect. Most significant IPA metabolic interaction network for the plasma metabolites correlated with polyp counts and associated with a Genotype by Diet interaction (listed in Table 3 and Additional file 9: Table S5). For metabolic pathways, an arrow pointing from node A to node B signifies that B is produced from A. The keys of molecule shapes and relationship labels show the nature of the nodes as and their relationships, respectively. Acronyms refer to relationship labels and numbers in parentheses next to them refer to the number of literature findings that support these relationships individually. Both direct (solid line) and indirect (broken line) specific relationships between the metabolites are indicated. Nodes with pink fillings represent metabolites that were significantly changed in the interaction effect and correlated with the outcome of interest. Metabolites involved in “Gastrointestinal Disease and Cancer” are circled in dark pink. Note in the top-left of the graph the presence of the hippuric acid metabolic pathway resulting from the conjugation of glycine with benzoic acid, which in turn is a conversion by-product of the L-phenylalanine metabolism.