Vegitarians were not Meant to Be

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.