What is one common symptom of dehydration?

Thirst or dry mouth is a common symptom of dehydration because these sensations are the body's primary signals that it needs more fluids. When the body lacks adequate hydration, it triggers thirst to encourage fluid intake, aiming to restore balance. Additionally, the mouth can become dry due to decreased saliva production as the body prioritizes its limited resources.

In contrast, excessive sweating typically occurs during physical activity or in hot environments and may actually lead to dehydration rather than indicate it. Frequent urination can be a sign of hydration, especially if one is drinking plenty of fluids, which would not indicate dehydration itself. Clear skin is generally associated with good hydration and health, rather than dehydration, where skin may become dry and lose elasticity.