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But that passage does more than simply carry the sweat to the surface. To avoid losing any more salt than necessary, the walls of the passage take salt out of the sweat so it can be reused by the body. So, when the sweat reaches the surface, it is less salty than when it was first produced in the sweat gland. The salt, itself doesn’t help keep you cool, but mixed with water to form sweat, the salt helps draw more water into the sweat gland. Sweating And Efficiency And the more you sweat, the more efficient the sweat glands get at removing the salt before the sweat leaves the body. If you go to a hot climate, you’ll find that after a few days, your sweat becomes less salty. People who live in hot climates may sweat more, but they lose less salt.