Potassium chloride

Potassium chloride is a crystalline salt made of potassium and chloride ions. In sports nutrition it supplies potassium, the main positively charged particle inside cells, and balances electrical signals and fluid movement.

Role in hydration and body function

Potassium works with sodium to maintain fluid inside and outside cells, support nerve impulses, regulate heartbeat and enable muscle contraction. Most of the body’s potassium is inside cells, while chloride helps maintain osmotic pressure and acid–base balance. Healthy kidneys hold on to potassium when intake is low and excrete excess; more than ninety percent of dietary potassium is absorbed. Sweat contains far less potassium than sodium or chloride, typically about 5 millimoles per litre, so losses during exercise are modest. Daily requirements for adults are about 3,500 mg potassium, and a normal diet rich in fruits, vegetables, legumes and dairy easily meets this need.

Examples and important facts

Potassium chloride is often used as a salt substitute in processed foods to lower sodium content. In sports drinks it appears in small amounts to replace the small amounts of potassium lost in sweat and to improve taste. Eating bananas, oranges, potatoes, beans, yogurt and leafy greens provides much more potassium than any sports drink. Guidelines for rehydration beverages suggest 2–5 millimoles of potassium and 20–30 millimoles of sodium per litre of fluid. People with kidney disease or those taking certain medications need to monitor potassium intake because high blood potassium can cause dangerous heart rhythms. For most athletes, a balanced diet provides all the potassium needed.

Potassium chloride is a simple way to supply potassium in a beverage or food. Because sweat losses are low, only a small amount is needed in a sports drink. Rich sources in regular foods and normal kidney function maintain adequate levels without special supplements.

Related Terms: potassium citrate, sodium chloride, sodium bicarbonate, magnesium citrate, hydration