Why it works

How sweating cools the body

Short answer

Sweat cools when it evaporates from skin; sweat that drips away without evaporating provides less cooling.

The simple explanation

  • Moving air can increase evaporation.
  • High humidity reduces it.
  • Sweating also loses water and salts, so hydration matters.

Why it works

This advice follows NHS guidance and the underlying principles of sweating and evaporation.

Important exceptions

Safety, health, weather and the design of your home can change what is appropriate. Stop if an action makes conditions worse.

Related guides

Sources & evidence

Reviewed 2026-08-21

  1. NHS: Dehydration

    Supports: Dehydration risks, signs, fluids and when to get help.

    health guidance · Accessed 2026-08-21