Sodium is an electrolyte that plays a role in many physiological processes, including nerve transmission and muscle contraction. Along with other electrolytes, sodium helps balance bodily fluids and facilitate the movement of materials across cell membranes

High sodium levels cause the body to retain fluid, which increases blood pressure, the force with which blood pushes against vessel walls. This additional force can damage the fine capillaries of the kidneys’ filtration units. Most people with high blood pressure have no symptoms, even if blood pressure readings reach dangerously high levels. High blood pressure usually develops over many years and can lead to serious problems, including heart attack and stroke. Excess sodium can also lead to calcium loss and osteoporosis.

Electrolytes have long been synonymous with brightly colored sports drinks, but in recent years, competitors like coconut water have been making inroads. The electrolyte such drinks usually tout is potassium and the comparison is usually made to having as much or more potassium than a banana (a particularly rich source of the mineral).

Potassium plays an important role in maintaining cardiac electrical activity. Both too little potassium (hypokalemia) and too much (hyperkalemia) can result in potentially dangerous arrhythmias (irregular heart beat).