Hydration levels significantly affect cognitive function, as even mild dehydration can impair attention, memory, and overall cognitive performance. Water plays a vital role in maintaining neural function and regulating temperature. Insufficient fluid intake can lead to fatigue, reduced alertness, and difficulty concentrating. In various studies, participants showed lower cognitive test scores when dehydrated compared to hydrated counterparts. To support optimal brain health, it is crucial to stay adequately hydrated throughout the day, particularly during stressful situations or physical exertion when fluid loss can be pronounced.