When drinking lots of water throughout the day, salts (especially sodium) are washed through the kidneys and voided. Increasing salt in the diet helps prevent any imbalance as a result of significant water consumption and low salt intake. For every two quarts of water consumed per day consider adding 1/2 teaspoon of salt.
Excessive sweating can lead to dilution of salt in body fluids which can cause a condition known as hyponatremia. Symptoms of hyponatremia are fatigue, weakness, cramping, nausea, vomiting, bloating, swelling and tightness of the hands and feet, dizziness, headache, confusion, fainting, seizures, coma, and even death. This is usually an acute problem encountered in athletic circumstances, requiring emergency medical care. Heat exhaustion and heat stroke must be distinquished as the treatment for each is different.