Scope: Biomarkers of red meat may clarify the relationship between meat intake and health. Herein we discover biomarkers of intake for three types of meat with varying heme content and further evaluate candidate biomarkers for red and general meat based on defined validation criteria.

Methods and results: In a randomized cross-over meal study healthy volunteers consumed a randomized sequence of four test meals: chicken, pork, beef and a control consisting of egg white and pea. Fasting and postprandial urine samples were collected for 48h and profiled by untargeted LC-ESI-qTOF-MS metabolomics. The profiles following the meal challenges were explored by univariate and multivariate analyses. Nine red-, four white- and eight general meat biomarkers were selected, originating from collagen degradation, meat aroma compounds, and amino acid metabolism. Heme-related metabolites were masked by the chlorophyll content of the control meal. The candidate biomarkers were confirmed in an independent meal study and validated for plausibility, robustness, time-response and prediction performance. Combinations of biomarkers were more efficient than single markers in predicting meat intake.

Conclusion: New combinations of partially validated biomarkers are proposed to assess terrestrial meat intake and thus help disentangle the effects of meat consumption on human health.