Genetic testing for assessing individual predisposition to diseases is often mentioned as the central tool in precision medicine. However, in most complex diseases, such as diabetes, known genetic factors explain only a relatively small fraction of a person’s actual risk.
Metabolite profiling of 100-1000 metabolites using modern metabolomics approaches provides a detailed readout of a person's physiological state, capturing the combined effect of genetic and variable extrinsic factors such as life style. Longitudinal metabolomics studies, assessing metabolite profiles at multiple time points from the same individuals, additionally allow focusing on individual molecular trajectories over time or on response to treatment.
Recent advances enabled this deep metabolic phenotyping on an epidemiological scale, opening new avenues to study human metabolism, its individuality, and its variation in health and disease based in thousands of subjects. Despite dynamic changes in metabolite profiles occurring on response to external stimuli such as food ingestion, we demonstrated that a person’s overall metabolite profile is an individual, usually very stable, characteristic. We also showed that changes in this personal metabolome associate with worse health outcomes, making metabolomics a promising tool for monitoring individual health and suggesting a paradigm shift from cross-sectional population-based to longitudinal patient-based „normal“ ranges.