How much salt is in a human body?

The percentage of salt in our bodies is very close to that of the ocean, so just how salty does that make us?

Asked by: Dan Down, by email

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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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