Abstract
Introduction: Brazil is undergoing rapid population aging, with individuals aged 60 and above comprising 15.6% of the population in 2023. This demographic shift poses significant publichealth challenges, particularly the rising prevalence of cognitive decline, compounded by widespread micronutrient deficiencies. Objective: To synthesize evidence on the relationship between micronutrient status, supplementation, and cognitive decline in older Brazilian population, and to identify barriers to implementing nutritional strategies into public health and clinical practice. Methods: A narrative review was conducted using data from national surveys, regional studies, clinical trials and reviews. Literature searches were performed in PubMed, MEDLINE, and Embase using Brazil-specific terms related to micronutrients, cognitive health, and aging. Results: Deficiencies in vitamins B-complex, D, E, and minerals such as magnesium, zinc, and selenium are prevalent among older Brazilians, with some inadequacy rates exceeding 60–80%. These deficiencies are mechanistically linked to cognitive decline via oxidative stress, neuroinflammation, and elevated homocysteine levels. Evidence from clinical trials, notably COSMOS, and the 2025 Latin American Consensus Statement supports multivitamin and mineral supplementation (MVMs) as an effective strategy to improve memory and cognition. However, key barriers include lack of age-specific dietary reference values, national supplementation guidelines, and systematic integration of nutrition into geriatric care. Conclusions: Addressing micronutrient deficiencies through targeted supplementation and nutrition policy reforms represents a practical, evidence-based approach to promote cognitive resilience and healthy aging in Brazil.