Micronutrients are essential for preserving brain health and adequate mental function. Their importance comes from their crucial effect on signal transduction, neural plasticity, neurogenesis, neurotransmitter synthesis, and brain development and evolution. Brain functions including memory, perception, and decision-making have all been found to be impacted by essential micronutrients deficiency, such as iron, zinc, iodine, and vitamins. On the other hand, sufficient consumption of these nutrients has been associated with enhanced cognitive performance and a decreased risk of neurodegenerative diseases. Recent studies demonstrate how micronutrient supplements may improve cognitive performance. It was found that effective nutritional supplementation can promote brain health and slow cognitive decline, and this requires an understanding of the interactions between micronutrients and cognitive functions. In this chapter, we shed light on the importance of micronutrients on brain health and how micronutrients deficiency affects brain function on all levels including cognition, memory, and perception.