We already know that the body contains a lot of water – in fact over 70% of the body is composed of water. But this isn’t pure water. It is a salt solution, and as we lose a certain amount of our body fluid every day, we also lose salt, which we must replace. We don’t get salt from vegetables and plant food, but we do get it from meat. This is why purely meat-eating animals don’t need extra salt, whereas those who eat only vegetation, such as cows, do need extra salt. Because most people eat both vegetables and meat, we only add a very little amount of salt to our meals. If we had no salt at all in our diet, we would soon go mad for lack of it.