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How does sweating cool the body through evaporation?

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water rapids, Niagara Falls, Canada — water Water is the most plentiful compound on Earth and is essential to life. Although water molecules are simple in structure (H₂O), the physical and chemical properties of water are extraordinarily complicated.

Sweating cools the body through the process of evaporation, which relies on the physical properties of water as a chemical compound.12

When the body's temperature rises, the sympathetic nervous system triggers eccrine sweat glands to secrete water onto the skin's surface. For this liquid water to transition into a gaseous state (vapour), it must absorb a significant amount of thermal energy from the body, known as the latent heat of vaporization.132

Because water has a high heat of vaporization, the energy required to break the cohesive forces between water molecules is substantial. As the sweat evaporates, it carries this absorbed thermal energy away from the skin, effectively lowering the body's temperature. This mechanism serves as a vital thermoregulation tool, allowing the body to dissipate heat and maintain a stable internal environment.321