As a student, I often wonder if it’s possible to die from sleep deprivation. I arrive at school in the morning and talk to my equally tired friends, then go to class, with the constant risk of falling asleep if a teacher turns the lights out for a movie. Most weeks, I sleep an average of five hours per night. The reasons for sleep deprivation in adolescents can range from hormonal time shift (the natural tendency to become sleepier later), busy schedules, and light exposure, among many others. While this is common among students, most adults require seven to nine hours of sleep, and adolescents generally need at least nine. By this point, I’m probably in thousands of hours worth of sleep debt, but there’s hope; evidence shows that sleep debt can be repaid.
A study with student volunteers conducted by University of Chicago had the volunteers sleep four hours per night for six days. The results showed increased blood pressure, increased level of cortisol (a stress hormone), and a decreased production of antibodies in response to a flu vaccine. When they repaid the hours of sleep they had forgone, the effects of sleep deprivation were reversed; all the adverse effects that came with sleep deprivation vanished again. A downside is that the only way to repay sleep debt is to actually sleep, which can be difficult when the extra time is difficult to find in a busy schedule.
Sleep is induced by an increased adenosine concentration (a neurotransmitter) as well as the circadian rhythm (a biological cycle that regulates sleep-wake patterns). As cells use energy, they release adenosine as a byproduct. High adenosine concentration reduces ability to focus, slows reactions, and negatively affects memory- all the common symptoms of being tired. When we sleep, less energy is required, and adenosine levels drop.
Despite the many adverse effects, there’s evidence against humans being able to die from lack of sleep. No one has ever been known to die from sleep deprivation, even after they had been awake for 449 hours. Other animals, however, are a different story. In this study, dogs developed brain lesions and died after only a few days of being kept awake. In rats as well, sleep deprivation can prove fatal. Humans seem to have developed mechanisms to prevent death in the event that they become severely sleep deprived. These mechanisms shut down part of the brain while the rest remains awake, resulting in microsleeps: brief episodes of sleep that last between less than one second to ten seconds.
Even though humans may not be able to die directly due to lack of sleep, these short episodes of sleep that result from sleep deprivation can be dangerous. It’s more healthy and more responsible to try to get as much sleep as possible in this hectic life, despite the obstacles that make it difficult.