Sodium makes up 40 percent of table salt so that 3000 mg of salt (about one level teaspoon or three packets of salt) contain 1200 mg of sodium, which is the ingredient listed on the label of all processed food. Most fresh foods have a low sodium content, but sodium is often added during food and beverage processing. In the American diet, this added sodium accounts for about 80 percent of a person’s total sodium intake.
Several lines of evidence strongly link a high sodium intake to hypertension. As an example, hypertension rarely occurs in countries in which people consume less than 1000 mg per day of sodium; it primarily occurs in countries in which people consume more than 2000 mg of sodium per day. Most Americans consume about 4000 milligrams of sodium per day.