2025/07/30 by Markus Arnoldini, Richa Sharma, Claudia Moresi +4 · 3 voices · 20 citations
Agricultural and Biological Sciences · Biochemistry, Genetics and Molecular Biology · Medicine · #Biochemistry #Biology #Biotechnology #Diet and metabolism studies #Fermentation #Food science #Gut flora #Gut microbiota and health #Microbiology #Probiotics and Fermented Foods
paper · pdf · doi:10.1016/j.cell.2025.07.005
published in Cell 188(19), 5332-5342.e16 (Cell Press)
openalex publication_date 2025/07/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Fermentation products released by the gut microbiota provide energy and regulatory functions to the host. Yet, little is known about the magnitude of this metabolic flux and its quantitative dependence on diet and microbiome composition. Here, we establish orthogonal approaches to consistently quantify this flux, integrating data on bacterial metabolism, digestive physiology, and metagenomics. From the nutrients fueling microbiota growth, most carbon ends up in fermentation products and is absorbed by the host. This harvest varies strongly with the amount of complex dietary carbohydrates and is largely independent of bacterial mucin and protein utilization. It covers 2%-5% of human energy demand for Western diets and up to 10% for non-Western diets. Microbiota composition has little impact on the total harvest but determines the amount of specific fermentation products. This consistent quantification of metabolic fluxes by our analysis framework is crucial to elucidate the gut microbiota's mechanistic functions in health and disease.