What it does
Potassium helps maintain fluid balance inside cells and contributes to nerve transmission and muscle contraction, including normal heart function. Needs are expressed as Adequate Intakes because the available evidence did not support setting an RDA for healthy populations.
Food sources and absorption
Beans and lentils, potatoes, leafy greens, squash, tomatoes, bananas, dried fruit, yogurt, milk, fish, and meat can contribute. A varied eating pattern often matters more than one famous “potassium food.”
Safety and individual context
Kidney disease and some medications can make high potassium dangerous. Salt substitutes often replace sodium chloride with potassium chloride. Do not use supplements or potassium-based salt substitutes as a universal fix; ask a clinician or pharmacist when kidney function or relevant medication is involved.
Primary reference
NIH Office of Dietary Supplements consumer fact sheet
How to use this information
Reference values describe population needs and are not a diagnosis. Food patterns, health conditions, pregnancy, laboratory results, and medications can change what is appropriate. Avoid high-dose supplementation unless there is a clear reason and qualified guidance.