Mondo Knows Facts
Sweat cools the body only as it evaporates
Each gram of water that turns to vapour carries away a large amount of heat Sweat glands release a watery fluid onto the skin, but the cooling happens at the moment of evaporation. Turning a gram of water into vapour takes about 2,400 joules at skin temperature, drawn from the body. In humid air evaporation slows, so the same sweat produces far less cooling. It sits in Mondo's human body collection, one of 200 facts that each trace back to the reference below.
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Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.
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Tags: heat, sweat, cooling
Sweat cools the body only as it evaporates: the short answers
- Where does this come from, and can I check it?
- Each gram of water that turns to vapour carries away a large amount of heat. The figure is taken from WHO, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
- Is this really a human body fact?
- Yes. It sits on the Human Body shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
- What else can I read about it?
- The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.