Sodium

This important mineral controls fluids in your body and helps regulate your heart and metabolism. Too little can cause muscle cramps, fatigue, nausea, and cognitive problems. Too much forces your heart to work harder. Sodium is found in nearly every processed food―even, counterintuitively, in sweets like doughnuts.

The middle ground: The American Heart Association recommends limiting sodium intake to less than 2,300 milligrams a day (about one teaspoon). African-Americans, people with hypertension, and those who are middle-aged and older need less than 1,500 milligrams a day. But the average American gets nearly double that. “The best way to reduce sodium is to minimize processed foods,” says Goodson. Then take the salt shaker off the table; if you need a flavor kick, try cumin, tarragon, or oregano.