Dehydration occurs when the body loses more fluids than it takes in, leading to various symptoms. Common signs include thirst, dry mouth, and reduced urine output. In mild cases, individuals may also experience fatigue and dizziness. As dehydration worsens, symptoms can escalate to include rapid heartbeat, confusion, and extreme thirst. Severe dehydration may lead to serious complications, such as heat exhaustion or kidney problems. It's essential to recognize these symptoms early and rehydrate by drinking fluids or consuming foods with high water content.