Association Between Mineral Intake and Cognitive Perfor-Mance in Spanish Adults: A Cross-Sectional Study

Background/Objectives: While adequate mineral intake is essential for brain health and cognitive function across the lifespan, the potential impact of excessive consumption remains underexplored. This study analyzed the association between dietary mineral intake and cognitive performance, with particular interest in how different intake levels may influence specific cognitive domains. Methods: A cross-sectional study was conducted in 239 Spanish adults (18–65 years) from the Tech4Diet-Person project. Sociodemographic, dietary, and cognitive data were collected between 2021 and 2024. Cognitive function was assessed using the validated computerized CogniFit battery, and mineral intake was estimated through a food frequency questionnaire (93 items). Individuals with neurological, metabolic, or psychiatric disorders, as well as pregnant or lactating women, were excluded. Results: Participants had a mean age of 45.85 (± 10.14) years, and 16% showed low cognitive performance, which was associated with older age and lower educational level. Higher iron intake was observed in individuals with lower global performance (p = 0.037), reasoning (p = 0.037), and cognitive flexibility (p = 0.037), while higher zinc intake was associated with impairments in working memory (p = 0.026). Iron intake was associated with greater odds of low cognitive performance (OR = 1.136; p = 0.011), independent of sociodemographic variables. Conclusions: Excessive intake of iron and zinc is associated with poorer cognitive performance, highlighting the importance of a balanced nutritional intake to preserve brain function throughout the lifespan.