Background:The development of numerous disease-modifying drugs for age-related dementia has been attempted based on the amyloid-β (Aβ) hypothesis without much success. Taxifolin (TAX), a natural bioactive flavonoid, shows pleiotropic neuroprotective effects with inhibition of Aβ aggregation, production, and glycation, antiinflammatory effects, and amelioration of the waste clearance system. We hypothesized that TAX intake is associated with the suppression of cognitive deterioration.Objective:To investigate associations between TAX intake and cognitive changes.Methods:We retrospectively identified patients who orally took TAX 300 mg/day and regularly underwent Alzheimer’s Disease Assessment Scale-Cognitive Subscale 13 (ADAS-Cog) and Montreal Cognitive Assessment (MoCA) and compared the temporal changes in ADAS-Cog and MoCA between the non-treatment (pre-TAX) period (180±100 days) and following treatment (on-TAX) period (180±100 days) from June 2020 to November 2021. Since some additional patients underwent the Mini-Mental State Examination (MMSE) instead of the MoCA at the beginning of the pre-TAX period, the same comparison was performed using the MoCA total score converted from MMSE as a sensitivity analysis.Results:Sixteen patients were identified. TAX intake was associated with significantly higher interval changes in the MoCA subscale scores of visuospatial/executive function (p= 0.016), verbal fluency (p= 0.02), and the total score (p= 0.034), but not with ADAS-Cog (total score,p= 0.27). In the sensitivity analysis, 29 patients were included. TAX intake was associated with a significantly higher interval change in the total MoCA score (p= 0.004) but not with ADAS-Cog (p= 0.41).Conclusion:Our findings provide a basis for TAX as a novel strategy for maintaining brain health during aging. A prospective cohort study is required to confirm these findings.