Human beings, it seems, learn about salt (and become addicted to it) at a very precise moment in their history: when they cease being almost exclusively carnivorous and learn to eat vegetables in quantities usually available only when they grow them themselves. When people begin not only to eat a lot of vegetables, but to reduce the salt content in their food by boiling it–a cooking method which presupposes the ability to make metal pots that can be set directly over a fire–hen salt becomes more desirable still.

Margaret Visser, Much Depends on Dinner – the extraordinary history and mythology, allure and obsessions, perils and taboos of an ordinary meal, 65.