KD reduced social-cognitive deficits and repetitive behaviours in BTBR miceReduced expression of TNFα, IL-1β, and IL-6 in plasma and prefrontal cortex of BTBR miceLipid peroxidation levels and superoxide dismutase activity altered in BTBR mice brainsRelative abundance of putatively beneficial microbiota seen in BTBR and control mice on KD. The gene discussed is IL1B; the disease is Cognitive impairment.