Ergothioneine for Cognitive Function

Research suggests that ergothioneine may support cognitive function and help protect against age-related neurodegeneration, with evidence spanning animal studies, human observational data, and early clinical work generally pointing in a supportive direction. Studies indicate that blood ergothioneine levels tend to be lower in individuals with dementia and cognitive impairment, that higher mushroom intake — a primary dietary source of ergothioneine — is associated with better cognitive test scores in older adults, and that supplementation in mice improved memory and neuronal health through antioxidant, anti-inflammatory, and mitochondrial mechanisms; one small human trial also found that ergothioneine supplementation correlated with improved scores across multiple cognitive tests alongside a measurable biological signal in the blood. The body of evidence currently reviewed includes a systematic review of 19 studies, several narrative reviews, animal model experiments, and human observational analyses, with one ongoing randomized controlled trial not yet reporting results — meaning the field lacks completed, large-scale clinical trials in humans. Limitations are significant: most mechanistic work comes from rodent models, human studies are largely observational and cannot establish causation, and one study found ergothioneine levels were altered in the context of schizophrenia-related cognitive changes in a complex, not straightforwardly beneficial, direction, underscoring that well-designed clinical trials are still needed before firm conclusions can be drawn.