Electrolytes are minerals that carry an electric charge when they dissolve in water or body fluids such as blood. The main ones in the body are sodium, potassium, chloride, calcium, magnesium, phosphate, and bicarbonate, and you get them from the foods you eat and the fluids you drink.
They help balance the amount of water in your body and its acid/base (pH) level, move nutrients into cells and wastes out of them, support muscle and nerve function, keep your heart rhythm steady and blood pressure stable, and keep bones and teeth healthy. An electrolyte imbalance means one or more levels are too high or too low, which can happen when the amount of water in your body changes, for example after heavy sweating, vomiting, or diarrhea.
Source: MedlinePlus: Fluid and Electrolyte Balance (U.S. National Library of Medicine).
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