Pulling an all-nighter could be just as damaging to your immune systems as physical stress, according to a new study.
Researchers from the Netherlands and the United Kingdom monitored changes that occurred in a type of white blood cell after severe lack of sleep. The small study involved 15 healthy men who were put through two stages—one week of normal sleep (eight hours per day) and 29 hours of sleep deprivation.
During the week of normal sleep, the men were exposed to 15 minutes of sunlight upon waking, and were limited in their intake of caffeine, medications, and alcohol. This stabilized their body’s natural clock—circadian rhythm—before their all-nighter.
During the period of sleep deprivation, the granulocytes—white blood cells that play a role in the body’s immune response—increased in number, especially at night. The levels also became less variable throughout the day. Normally, granulocytes change in number between night and day.
"The granulocytes reacted immediately to the physical stress of sleep loss and directly mirrored the body's stress response," Katrin Ackermann, a postdoctoral researcher working on the study, said in a news release.
The study was small, so more research will be needed to determine what role these sleep-related immune system changes may play in chronic diseases like obesity, diabetes, and hypertension.
Previous research, though, has linked adequate amounts of sleep to healthy immune systems. This could have a potential impact on how sleep deprivation is treated by doctors, as well as provide insight into how shift work affects employees.