Salt is a magical substance. It reduces bitterness, enhances sweetness, boosts flavor, and preserves perishable foods. Without it, we would die: The human body can't make sodium, but our nerves and muscles don't work without it. It was considered rare until quite recently, so it's hardly surprising that, throughout history, salt has been the engine behind empires and revolutions. Today, there's a new battle in the salt wars, between those who think that we eat too much of it and it's killing us—and those who think most of us are just fine. Join us for a serving of salt, seasoned with science, history, and a little politics.
One of salt's many mysteries is how our ancestors first figured out that they needed it: unlike hunger or thirst, someone suffering a sodium deficiency doesn't crave salt. What's more, until humans began farming, we had no need to add salt to our diets—even today, Masai hunter-gatherers can get enough salt simply by drinking the blood of their livestock. But, however our need for salt was discovered, extracting it and trading it has shaped human history. From the very first brine wells in Sichuan province, China, to Mahatma Gandhi and the Indian independence movement, author Mark Kurlansky helps us trace the impact of salt through language, taxation, cuisine, and empire.