Heat exhaustion is primarily due to the loss of which substances?

Heat exhaustion is primarily associated with the loss of both sodium and water from the body due to prolonged exposure to high temperatures, particularly when one engages in vigorous physical activity without sufficient fluid and electrolyte intake. When the body overheats, it initiates sweating as a physiological response to cool down. This sweating leads to the loss of water and essential electrolytes, especially sodium, which is critical for maintaining fluid balance and proper cellular function.

During heat exhaustion, the combination of water loss and sodium loss can lead to dehydration and electrolyte imbalances, resulting in symptoms such as weakness, dizziness, and confusion. Thus, the correct answer is the loss of both sodium and water, underscoring the importance of replenishing both fluids and electrolytes when recovering from heat-related illness.

The other options are less accurate because they focus exclusively on one substance or another. For instance, stating sodium only would neglect the fluid loss aspect, and emphasizing water only would ignore the critical role of sodium in maintaining electrolyte balance. Potassium and magnesium are also not primarily lost in significant amounts during heat exhaustion compared to sodium.