Thesleep deprivationmakes theimmune system kicks in, reflecting the same kind of immediate response that takes place after exposure to stress, according to a new study published in the journalSleep.
In the new research, scientists from the Netherlands and the United Kingdom havecompared the white blood cell counts of 15 healthy young men in normal conditions and in severe sleep deprivation conditions. The greatest changes were seen in white blood cells known as granulocytes, which showed a loss of day-night rhythm. As explained by Katrin Ackerman, lead author of the study, “future research will reveal the molecular mechanisms underlying this immediate response to stress, and describe its role in the development of diseases associated with chronic sleep loss.”
Some previous studies have linked sleep restriction and deprivation with the development of diseases such as obesity, diabetes, and hypertension; while others have shown that sleep helps support the functioning of the immune system, and that chronic sleep loss is a risk factor for its deterioration.
In the new research, the white blood cells of the 15 subjects were measured and analyzed after a strict eight-hour sleep schedule, every day, for a week. The participants were then exposed to at least 15 minutes of light outdoors within the first 90 minutes of wakefulness, and the use of caffeine, alcohol, or medications was prohibited for the last three days. This study was designed to stabilize circadian clocks, and minimize sleep deprivation, prior to intensive laboratory study.
Subsequently, the white blood cell count in a normal sleep-wake cycle was compared with data from the second part of the experiment, in which blood samples were collected during 29 hours of continuous wakefulness. As a result, Ackerman concludes,granulocytes reacted immediately to the physical stress of sleep loss.
