Common signs of dehydration include thirst, dark urine, dry mouth, fatigue, and dizziness. In more severe cases, symptoms may escalate to headache, rapid heartbeat, and confusion. Staying adequately hydrated is crucial for maintaining physical and cognitive performance, especially during exercise. Recognizing these signs early can help prevent serious complications and promote better health outcomes. Monitoring fluid intake, particularly during hot weather or strenuous activities, is essential for active individuals.