Dehydration

Dehydration (dehydration): When the body lacks water

Dehydration is a condition in which the body loses more fluid than it takes in, leading to a negative water balance. Water is the basis of life and makes up more than 60% of an adult's body weight and up to 75% in infants. It participates in all key processes: transport of nutrients, regulation of body temperature, elimination of toxins, and support of all organ functions. Even a slight fluid deficit can significantly affect well‑being, and severe dehydration is a life‑threatening condition.

Why does dehydration occur?

Dehydration is rooted in an imbalance between fluid intake and loss. This imbalance can be caused by two main reasons:

• Insufficient fluid intake: The person simply does not drink enough water. This may be due to lack of access to water, nausea or loss of appetite during illness, or ignoring thirst signals.
• Excessive fluid loss: This is the most common cause. The body can lose fluid through several pathways:
  • Through the gastrointestinal tract: Vomiting and diarrhea are the main culprits, especially in children.
  • Through the skin: Intense sweating during heat, physical exertion, or at high temperature.
  • Through breathing: During fever, breathing becomes faster, which also increases fluid loss.
  • Through urine: Use of diuretics or certain diseases such as uncontrolled diabetes mellitus.

Symptoms and degrees of dehydration

Symptoms depend on the degree of fluid deficit:

• Mild degree: Thirst, dry mouth, reduced urine volume and darkening of urine.
• Moderate degree: Strong thirst, dizziness, headache, weakness, rapid heartbeat, significant reduction in urination.
• Severe degree: Confusion, loss of skin elasticity, sunken eyes, absence of tears and urine, possible loss of consciousness. This condition requires immediate medical attention.

Dehydration is closely linked to electrolyte imbalance, because vital salts are lost along with fluid. Dehydration in young children is especially dangerous, as described in detail in the article "Dehydration in children".