Risiko-Rechner für Dehydration

Common signs include dark yellow urine, dry mouth, headache, fatigue, dizziness, and reduced urine output. Severe dehydration can cause rapid heartbeat, sunken eyes, and confusion. Thirst itself is already a late signal — by the time you feel thirsty, you may already be mildly dehydrated.

Caffeine has a mild diuretic effect, but moderate coffee consumption (3-4 cups per day) does not cause significant dehydration. The water in coffee partially offsets the diuretic effect. However, each cup does increase your total fluid needs by roughly 150 ml.

Drinking more than 1 litre per hour over several hours can lead to hyponatremia (dangerously low blood sodium). For most people, staying under 3-4 litres per day spread evenly is safe. Athletes and people in hot climates may need more but should also replace electrolytes.

Yes. Electrolytes (sodium, potassium, magnesium) help your body absorb and retain water more effectively. If you exercise heavily, sweat a lot, or drink large amounts of plain water, adding electrolytes can improve hydration status and prevent imbalances.