Potassium
Potassium (K)
Minerals. Modern nutrition.
Also called Potassium chloride, Potassium citrate, Potassium gluconate, Potassium bicarbonate
Pinyin: jiǎ
Spanish: Potasio
Can cause dangerous heart rhythmsA mineral that helps nerves, muscles and the heart work, and helps keep fluids and blood pressure in balance.
Did you know? Most of the body's potassium sits inside cells. The difference between inside and outside levels creates the electric charge that lets nerves fire and the heart beat.
What it may help, and how strong the proof is
- Blood pressure. Diets rich in potassium from fruits and vegetables lower blood pressure in many trials. Potassium-enriched salt has also lowered blood pressure in trials. The effect is modest, and pills are not the same as food.Good proof
- Kidneys, bladder & UTIs. Doctors prescribe potassium citrate to help prevent some kidney stones, and several trials support this. Do not use it on your own, since it can raise blood potassium to dangerous levels.Good proof
Parts of the body
Traditional use
Coconut water is a folk drink in tropical countries, valued for fluids and potassium. Potatoes and beans were staple potassium sources in Andean and Mesoamerican diets for centuries.
How it is classified
- Herbal actions
- Nutritive, Hypotensive. Energy: neutral.
How people take it
Adequate intake (AI), used when no RDA is set, is 3,400 mg a day for men and 2,600 mg a day for women ages 19 and up. These values come from 2019 National Academies guidance. No upper limit has been set for potassium from food. Over-the-counter pills in the US are limited to 99 mg, because larger pills can irritate the gut.
Food, tablet and powder.
Where to get it
Good sources are potatoes with skin, sweet potatoes, white beans, lima beans, lentils, spinach and beet greens, avocado, bananas, dried apricots, yogurt, milk, salmon, tomato paste, and coconut water. Pills are uncommon, and prescription potassium chloride is the usual form.
Be careful
Potassium from food is safe for most people. Pills can irritate the stomach, and too much potassium in the blood can cause dangerous heart rhythms, especially with kidney disease or some blood pressure medicines.
Avoid if: kidney disease; high blood potassium; ACE inhibitors or ARBs.
Mixing with other things
- Works well together
Low magnesium makes low potassium harder to correct, so the two are often checked together.
- Don't mixBlood pressure medicine (lisinopril, amlodipine, losartan)
ACE inhibitor and ARB blood pressure drugs raise blood potassium. Do not add potassium pills unless a doctor says so and checks levels.
- Don't mixWater pills (furosemide, hydrochlorothiazide)
Potassium-sparing water pills (spironolactone, amiloride) keep potassium in the body, so extra potassium can reach dangerous levels. Thiazide water pills do the opposite and can lower potassium.
Adds up with others that may lower blood pressure: , , , , , , , , , , , , , and 12 more.
The honest take
Potassium from food is essential, and most adults do not get enough. Pills are a different story, because they can irritate the gut and push blood levels too high. Claims that potassium pills lower blood pressure should be left to doctors, who can check blood levels.