Diet–gut microbiota interactions in metabolic resilience: from microbial metabolites to precision nutrition

Nutrition influences metabolic homeostasis through interactions among dietary patterns, gut microbial function, metabolite production, cellular stress, and immune regulation. However, the factors determining whether nutritional exposures support metabolic resilience or contribute to disease progression remain incompletely understood. This review synthesizes human and experimental evidence on how dietary patterns shape gut microbial function and metabolite production and how these microbial outputs relate to oxidative balance, proteostasis, and inflammatory signaling. It distinguishes microbial composition from functional activity, association from causation, and mechanistic plausibility from clinical relevance. Although current evidence supports functional roles for diet–microbiota interactions and microbial metabolites in metabolic regulation, reported effects vary across individuals and biological contexts. Methodological heterogeneity, limited longitudinal evidence, and incomplete translation of experimental findings constrain mechanistic interpretation in humans. Precision nutrition may help address this variability by integrating dietary assessment with microbiome function, metabolomics, metabolic phenotyping, and immune profiling. Its clinical value will depend on biomarkers and reproducible biological signatures that improve prediction and inform interventions beyond established dietary principles. Progress will require longitudinal studies, including controlled interventions, that link multi-omics profiles to meaningful metabolic and clinical outcomes.