Even people who have relatively little trouble with asthma during the day can have major difficulties at night. The reason: the body's 24-hour, or circadian, cycle. "In people with normal lungs, lung function falls during sleep--but only by about 8 percent, so it isn't a problem," says Dr. Martin. "But in asthmatics, lung function can fall by as much as 50 percent during sleep--with dire consequences. "
In addition, certain natural hormones that reduce inflammation and promote airway
