Sodium, or salt, has been valued throughout history. The word "salt" is the source of the English word "salary," which originally referred to money paid to soldiers to buy salt. Yet this value placed on salt has possibly led to its overuse in industrial society. For millions of years, the human species lived on a natural diet containing less than 1 gram per day of sodium, and elevated blood pressure was very rare. Nowadays, 6-12 grams and even higher amounts of salt per day are consumed by people eating processed and snack foods or as salt added in cooking and preparing foods. Salt itself is 40 percent sodium and 60 percent chloride. Therefore, 5 grams of salt (about one teaspoon) contain approximately 2 grams of sodium.