Polysaccharides from Tricholoma mongolicum, a rare edible mushroom, helped reverse metabolic fatty liver disease (MAFLD) in mice by restoring gut balance and blocking oxidative cell death. The extract reshaped gut microbiota, increased helpful metabolites, and suppressed ferroptosis, an iron-driven form of cell damage. This gut-liver axis approach offers a promising fungal path to protect against liver inflammation and metabolic dysfunction.