What happens to the immune system when we lose sleep?
Researchers have pinpointed how sleep deprivation can sabotage the immune system. The finding is significant because it shows lack of sleep has the same ill effect on the body as physical stress.
Physical stress from sleep loss found in blood tests
For the study, researchers measured white blood cell counts in 15 healthy men and women when they were sleep deprived and under normal sleep conditions.
White blood cells, also known as leukocytes, defend the body by producing antibodies that fight disease. There are five types of white blood cells.
Researchers specifically found higher numbers of granulocytes and loss of rhythm in the ways the cells that surround and destroy bacteria in the bloodstream are produced. Granulocytes are also the most numerous type of white blood cell in humans.
Blood samples for the study were collected during normal sleep cycles and then compared to granulocyte counts obtained during 29 hours of wakefulness.
"The granulocytes reacted immediately to the physical stress of sleep loss and directly mirrored the body's stress response," said Ackermann.
Sleep and immunity
Mayo Clinic expert, Timothy Morgenthaler, M.D., explains why sleep is important for fighting disease. During sleep, proteins, known as cytokines that fight infection are released.
Sleeping too much is linked to a variety of health problems, including obesity and heart disease and depression. Adults should try to get 7 to 8 hours of quality sleep each night for optimal health.
"Future research will reveal the molecular mechanisms behind this immediate stress response and elucidate its role in the development of diseases associated with chronic sleep loss," said Katrin Ackermann, PhD, the study's lead author in a press release.
"If confirmed with more data, this will have implications for clinical practice and for professions associated with long-term sleep loss, such as rotating shift work."
Sleep deprivation affects the immune system in the same way as acute physical stress; shown in the study. Lack of sleep activates the immune system, causing white blood cell counts to go up and lose their cyclic rhythm. The long-term effect of sleep deprivation could contribute to diseases in ways not previously understood.
"Diurnal Rhythms in Blood Cell Populations and the Effect of Acute Sleep Deprivation in Healthy Young Men"
June 30, 2012
Katrin Ackermann, PhD, et al.
Mayo Clinic: Insomnia
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