Science
How does sweating work?
Sweating works to cool your body: glands release watery sweat onto your skin, and as it evaporates it carries heat away. It's your built-in air conditioning, keeping your temperature steady when you're hot or exercising.
See it in motion.
Watch a 2-minute animated lesson that shows exactly how sweating works.
Step by step
- 1Sweat glands release fluid onto the skin's surface.
- 2As the sweat evaporates, it absorbs heat and cools you.
- 3The brain triggers it when body temperature rises.
- 4It also helps flush out a small amount of salt and waste.
- 5High humidity slows evaporation, making cooling less effective.
Frequently asked questions
- How does sweating cool you down?
- Evaporating sweat draws heat from your skin, carrying it away — so the body left behind is cooler.
- Why do you sweat more in humid weather?
- Humid air is already moist, so sweat evaporates slowly; you keep sweating but cool less, which is why humidity feels worse.
- Why does sweat taste salty?
- Sweat contains salts (electrolytes) from your body; most are reabsorbed, but some reach the surface, giving the salty taste.