Thirst

Definition

Physiological mechanism for regulating water intake that signals the need to consume water to compensate for losses.

How it works

Thirst is a regulated process controlled by the hypothalamus in response to two main stimuli: an increase in plasma osmolarity and a decrease in blood volume.

Role

Signals the need for water intake to prevent dehydration.

Examples

• Feeling after physical activity • Increased thirst during fever • Reduced sensation in older adults • Suppression during intense exercise

Recommendations

Do not wait for thirst to drink, especially in older adults or during exercise.

Key takeaway

Thirst is an important but incomplete signal that must be complemented by planned hydration.

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