Background: Strawberries have been identified to have antioxidant and anti-inflammatory properties that improve neuronal function and cognition, mostly in animal studies. It is unknown if the consumption of strawberries or related bioactives may reduce the risk of Alzheimer's dementia risk.
Material and methods: The study was conducted in 925 participants, aged 58-98 years of the Rush Memory and Aging Project. Participants were dementia-free at baseline, completed a food frequency questionnaire, and had at least two annual neurological evaluations. The diagnosis of Alzheimer's dementia was based on structured clinical neurological examination and standardized diagnostic criteria. The association of strawberry intake and incident Alzheimer's dementia was analyzed using proportional hazard models adjusted for age, sex, education, physical activity, participation in cognitive activities, APOE-ɛ4 genotype, dietary intake of other fruits, and total calorie intake.
Results: A total of 245 participants developed Alzheimer's dementia over the mean follow-up of 6.7 (±3.6) years. Higher strawberry intake was associated with reduced risk of Alzheimer's dementia (HR = 0.76, 95% CI: 0.60-0.96). In separate adjusted models, highest vs. lowest quartile intakes of Vitamin C (HR = 0.64, 95% CI: 0.45, 0.92), Pelargonidin (0.63, 95% CI: 0.43, 0.92), total anthocyanidins (0.69, 95% CI: 0.48, 0.99), and total flavonoids (0.67, 95% CI: 0.46, 0.98) were each associated with lower Alzheimer's dementia risk. These associations remained after further adjustment for cardiovascular conditions.
Conclusion: Consumption of strawberries and foods rich in vitamin C, pelargonidin, anthocyanidins, and total flavonoids may reduce the risk of Alzheimer's dementia.
Keywords: APOE-ɛ4; cyanidins; diet; flavonoids; pelargonidin; proanthocyanidins.