How much salt is in a human body?

Wednesday 22nd July 2009
Submitted by Len Fisher
Dan Down, by email

The human body contains many salts, of which sodium chloride (AKA common table salt) is the major one, making up around 0.4 per cent of the body's weight at a concentration pretty well equivalent to that in seawater. So a 50kg person would contain around 200g of sodium chloride - around 40 teaspoons. Since we lose salt whenever we sweat, it has to be continually replaced.

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