Food metabolomics applied in cohorts to accelerate the discovery of nutritional biomarkers

The purpose of dietary assessment is to estimate usual and recent intake of foods, nutrients, bioactive compounds and food contaminants for exploration of associations with health outcomes and monitoring of population nutritional status. These data are still extremely difficult to obtain. Methods currently used are based on dietary questionnaires which have inherent limitations linked to self-reporting. A complementary approach to questionnaires is the use of biomarkers. However, only a few biomarkers have been properly validated, which do not cover the wide range of foods consumed. Metabolomics has emerged as a promising approach to discover nutritional biomarkers. Typically, plasma or urine samples collected before and after acute intake of a specific food are profiled using NMR or high resolution Mass Spectrometry (MS) and compared using multivariate statistics to pinpoint the signals reflecting the consumption of the target food. In a proof-of-concept study on citrus, we showed that urine profiling of cohort subjects stratified by consumption could be a more effective strategy for discovery of sensitive biomarkers of intake.