Background: Obesity is a multifactorial epidemic linked to disruptions in gut microbial ecology. Plant foods, rich in dietary fibre, polyphenols, and bioactive phytochemicals, exert profound modulatory effects on the gut microbiome, with consequent impacts on metabolic homeostasis and adiposity.

Objective: This review synthesises evidence on how plant food-derived nutrients reshape gut microbial communities, alter short-chain fatty acid (SCFA) production, and modulate obesity-associated metabolic pathways.

Methods: A narrative review of randomised controlled trials, cohort studies, and mechanistic investigations published between 2020 and 2025 was conducted using PubMed, Scopus, and Web of Science databases.

Results: Plant-rich dietary patterns consistently enriched beneficial taxa (Akkermansia muciniphila, Bifidobacterium, Faecalibacterium prausnitzii), augmented SCFA production, strengthened gut barrier function, and reduced systemic inflammation in obese individuals. Dietary interventions, including prebiotic fibre, polyphenols, fermented plant foods, and the Mediterranean diet, demonstrated significant microbiome-mediated weight loss benefits.

Conclusion: Microbiome-targeted nutritional strategies using plant foods represent a promising, evidence-based approach for obesity management. Future precision nutrition models integrating individual microbiome profiling are warranted.