How can heavy perspiration lead to sodium deficiency?

Heavy perspiration can lead to sodium deficiency because sodium is an essential electrolyte that is lost from the body through the skin during sweating.12

When an individual experiences prolonged heavy perspiration—often due to excessive heat or high-intensity physical exertion—the body loses both water and sodium. If these losses are significant, they can reduce the body's sodium levels to the point where normal activity patterns are disrupted, a condition sometimes referred to as hyponatremia when blood sodium levels become abnormally low.324

Symptoms of this depletion may include muscle cramps, weakness, apathy, nausea, and dizziness. To prevent or treat this deficiency, it is important to replenish lost sodium by consuming salted foods or beverages containing sodium, such as sports drinks.32