What's the Difference Between Salt and Water in the Body?

A 70 kilo person has about 70 000 milligrams of sodium within their body. Only a very small amount sits inside ourselves it's only about 5% of all the sodium. The remaining 45ish percent is bound up in structures that we call 'osmotically inactive' These include on the inner lining of our blood vessels but also in our muscles and these protein structures within our skin.