The answer so far
Potassium is a mineral found in many foods. The body uses it for nerve signals, muscle contraction and normal heart and kidney function. Both low and high blood potassium can be harmful. People with kidney disease or taking medicines that affect potassium should ask a healthcare professional before using potassium supplements or salt substitutes.1
What potassium does
Potassium helps cells work, including the cells involved in nerve messages, muscle contraction and heart function. The kidneys help regulate the amount in the body.1
Where it comes from
Potassium is found in many foods, including potatoes, beans and lentils, fruit, vegetables, milk and yogurt. A varied diet is one way to obtain it; individual dietary advice can differ.1
Kidneys, medicines and supplements
Kidney disease and some medicines can make potassium build up. Potassium supplements and salt substitutes containing potassium can be unsafe for some people. Ask a healthcare professional before using them if you have kidney disease or take medicines that affect potassium.1
Sources
Selected supporting sources; this is not a complete literature review.
- Potassium: fact sheet for consumersNIH Office of Dietary Supplements · US government nutrition fact sheet