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.

Red and processed meat consumption within two different dietary patterns: Effect on the colon microbial community and volatile metabolites in pigs

Pigs were fed either red and processed meat or chicken meat within either a prudent or a Western dietary pattern for four weeks (2 × 2 full factorial design). The colon microbial community and volatile organic compounds were assessed (either quantified or based on their presence). Results show that Lactobacilli were characteristic for the chicken × prudent dietary pattern treatment and Paraprevotella for the red and processed meat × prudent dietary pattern treatment. Enterobacteriaceae and Desulfovibrio were characteristic for the chicken × Western dietary pattern treatment and Butyrivibrio for the red and processed meat × Western dietary pattern treatment. Campylobacter was characteristic for chicken consumption and Clostridium XIVa for red and processed meat, irrespective of the dietary pattern. Ethyl valerate and 1-methylthio-propane were observed more frequently in pigs fed red and processed meat compared to chicken meat. The prevalence of 3-methylbutanal was >80% for pigs receiving a Western dietary pattern, whereas for pigs fed a prudent dietary pattern the prevalence was <35%. The concentration of butanoic acid was significantly higher when the prudent dietary pattern was given, compared to the Western dietary pattern, but no differences for other short chain fatty acids or protein fermentation products were observed.