The relationship between micronutrients and cognitive ability in an elderly population with mild cognitive impairment and Alzheimer's disease: a cross-sectional study

Abstract Background: Mild cognitive impairment (MCI) and Alzheimer's disease (AD) are significant neurodegenerative disorders with increasing prevalence worldwide. Lifestyle and dietary factors, including micronutrients, have been suggested as modifiable risk factors for disease development. This study aims to investigate the association between micronutrients and cognitive ability in these diseases. Methods: A cross-sectional, randomized controlled study was conducted, involving 105 participants with MCI and AD. Dietary assessments were performed using a validated food frequency questionnaire, and micronutrient intake was calculated based on nutrient content. Disease severity was evaluated using the Functional Assessment Staging Tool (FAST). Statistical analyses, including correlation coefficients and multiple regression models, were employed to examine the association between micronutrients and disease progression. Results: The results revealed significant correlations between disease severity and several micronutrients, including omega-3 fatty acids (B = -0.2, P = 0.01), carotenoids (B = -0.19, P = 0.02), antioxidants (B = -0.19, P = 0.02), selenium (B = -0.17, P = 0.03), alpha-carotene (B = -0.16, P = 0.04), beta-carotene (B = -0.17, P = 0.03), and lycopene (B = -0.16, P = 0.04). Multivariate regression analysis showed that higher intake of omega-3 fatty acids was associated with slower disease progression. Furthermore, the levels of these micronutrients declined in advanced stages of the disease. Conclusion: Omega-3 fatty acids, carotenoids, and antioxidants may affect the cognitive ability and disease progression. Further longitudinal studies are warranted to establish causality and explore the therapeutic implications of these findings for the prevention and management of MCI and AD.