Untargeted Metabolomics to Reveal Red versus White Meat–Associated Gut Metabolites in a Prudent and Western Dietary Context

Scope
To improve understanding of the epidemiological link between red and processed meat consumption and chronic diseases, more insight into the formation of metabolites during meat digestion is warranted.

Methods and results
Untargeted mass-spectrometry-based metabolomics is applied to explore the impact of red and processed meat consumption (compared to chicken), combined with a prudent or Western dietary pattern. A pig feeding study (n = 32), as a sentinel for humans, is conducted in a 2 × 2 factorial design for 4 weeks. The luminal content of the small intestine and colon are collected to determine their metabolic fingerprints. Seventy-six metabolites (38 in the small intestine, 32 in the colon, and 6 in both intestinal compartments) contributing to the distinct gut metabolic profiles of pigs fed either chicken or red and processed meat are (tentatively) identified. Consumption of red and processed meat results in higher levels of short- and medium-chain acylcarnitines and 3-dehydroxycarnitine, irrespective of dietary context, whereas long-chain acylcarnitines and monoacylglycerols are associated with the red and processed Western diet.

Conclusion
The identification of red and processed meat–associated gut metabolites in this study contributes to the understanding of meat digestion in a complex but controlled dietary context and its potential health effects.