Where it comes from: Potassium is a mineral that's crucial for life—it’s necessary for the heart, kidneys and other organs to work normally. Certain foods, such as bananas, avocados, nuts (like almonds and peanuts), citrus fruits, leafy vegetables, milk and potatoes, are high in potassium. Potassium supplements are available in liquids, tablets, or capsules.
What it’ll do for you: “Potassium is one of the major minerals responsible for regulating fluids and mineral balance in and out of body cells,” explains Sari Greaves, RD, spokesperson for the American Dietetic Association and Nutrition Director at Step Ahead Weight Loss Center in Bedminster, NJ. It also helps transmit nerve impulses and helps muscles contract. But potassium is probably most known for regulating the heart (possibly preventing strokes) and maintaining normal blood pressure by blunting sodium's effect on blood pressure.
“Laboratory studies support the claims that potassium is beneficial when it comes to blood pressure control and preventing strokes but more research is needed,” adds Greaves.
Suggested intake: The Adequate Intake for adults is 4,700 milligrams daily. People who eat a healthy diet should get enough potassium naturally. However, those who eat mostly processed foods—instead of whole foods—tend to be up to 1,000 milligrams short of potassium. (Some medications for blood pressure could also cause a potassium deficiency, so check with your doctor.) A deficiency can cause elevated blood pressure and muscle cramps (those painful Charley horses!). Low potassium is also associated with a risk of high blood pressure, heart disease, stroke, arthritis, cancer, digestive disorders and infertility.
Supplements can build up in the body and damage the heart. Over-the-counter doses provide no more than 99 milligrams per serving, as mandated by the FDA because of these potential dangers with self-dosing. Greaves warns: “Because of possible serious adverse effects, potassium supplements should only be taken when prescribed by a physician.” Since food is the best way to get potassium, Greaves supplied this handy chart to help you track your intake:
- 1 medium banana: 420 mg
- 1 cup fat-free milk: 380 mg
- 1/2 cup cooked kidney beans: 360 mg
- 3 ounces cooked haddock: 340
- 2 ounce Baked potato with skin: 330 mg
- 3 ounces roasted skinless turkey: 225 mg
- 24 almonds: 210 mg
Associated risks/scrutiny: “Harmful effects from consuming too much potassium from food is rare because excess amounts are usually excreted,” says Greaves. “If an excess can't be excreted, it can cause heart problems and possible sudden death. People with kidney problems may be advised to limit potassium-containing foods.”
As stated above, potassium supplements can cause heart damage and should only be taken under the supervision of a doctor.