People with cystic fibrosis (CF) lose excessive amounts of salt when they sweat. This can upset the balance of minerals in the blood and result in dehydration. My son has CF and the doctors have always suggested that I make salty snacks readily available to my son, but no one has ever talked to me about dehydration.
Dehydration didn't become an issue until the year my son made the 7th grade basketball team. We were thrilled with his achievement, but it was definitely a bitter sweet experience. The good news is his lung function test scores shot up! However, the team played hard for two hours a day, 5 times a week. The rest of the kids went home tired and hungry, but our son would regularly fall into bed experiencing flu-like symptoms. Even though he didn't have a fever, he'd experience uncontrollable shivering. I was so focused on his lungs that I thought he was stirring up infected mucus, which resulted in these intense symptoms. However, the very next morning he'd climb out of bed feeling good enough to go to school.