Impact of Animal Protein and Plant Protein on the Gut Microbiota and Metabolites of C57BL/6J Mice

Plant-derived protein has gained popularity in recent years due to its health and environmental impact. Studies comparing the health benefits of animal and plant protein have mostly focused on soy as a plant protein representative due to its popularity. Demand for other protein sources such as peas and fava beans has been increasing; thus, the health impact of plant protein sources other than soy must be assessed. Evidence has shown that diet influences the gut microbiota and the metabolites in the body. Metabolites associated with amino acids are strong contributors to the metabolite distinction between dietary animal and plant foods. Certain gut bacteria are also known to be able to metabolize amino acids, thus influencing their survival in the gut. To discern the impact of plant and animal-based proteins, namely soy, pea, faba bean, beef, chicken, and pork, on the host gut microbiota as well as the metabolic profile, male C57BL/6J mice were fed with the proteins for 8 weeks. Results showed that each protein source influenced the gut microbiota and metabolic profile differently. However, these impacts were not caused by the amino acid profile alone. Other factors, such as myoglobin in meats and phenolic compounds in plant proteins, also play a role