Micronutrient balance and brain function: neuropsychological, metabolic, and clinical interactions.

Micronutrients, encompassing both vitamins and trace elements, play a central role in brain development, metabolic homeostasis, and cognitive performance from early life through old age. Rather than acting solely as enzyme cofactors or antioxidants, many of these nutrients influence transcriptional programs, shape synaptic signaling, and participate in neuroimmune and neuroendocrine crosstalk, and observational, interventional, and experimental studies now show that both deficiency and excess of specific micronutrients are linked to changes in memory, mood, attention, and executive function, as well as increased vulnerability to neurodevelopmental, neurodegenerative, and affective disorders. In this narrative review, we summarize mechanistic and clinical evidence on the contribution of key vitamins (A, D, E, C, B-complex, and choline) and minerals (iron, zinc, iodine, magnesium, selenium, copper, among others) to brain function, highlighting shared molecular pathways related to neuroplasticity, synaptic integrity, energy metabolism, oxidative balance, and neuroinflammation, and examining how micronutrient status interacts with aging, genetic variation, and lifestyle factors such as physical activity and diet. We also discuss the neurological and neuropsychological consequences of micronutrient imbalance and the potential of targeted, personalized nutritional strategies for brain health promotion and disease prevention in vulnerable groups and across diverse settings, arguing that clarifying these interactions provides a framework for integrating micronutrient assessment into multidomain approaches to preserve cognitive function and mental wellbeing throughout the lifespan.