Most Americans eat way too much salt, and people with salt-sensitive medical conditions consume twice as much as they should, Scientific American reports. The American average is 3,456 milligrams per day. The FDA guideline for someone not at risk is 2,300 milligrams, or one teaspoon. For older people, African Americans, and people with hiogh blood pressure—about two-thirds of the population—that number is 1,500 milligrams. (More salt stories.)