High resolution 1H-NMR and mass spectrometry provides an approach to investigate complex metabolic effects of diet. Traditional methods to investigate interactive effects of chemical exposure have relied upon detection of specific pathologic and physiologic responses for combinations with specific biologic activities. An alternate approach is to use available high resolution metabolic analyses (22) combined with bioinformatic tools, to examine metabolic effects of chemical interactions in a global manner. In principle, by simultaneously examining effects on hundreds of metabolites, this approach provides the possibility to detect unanticipated interactive effects.