There’s a great Q&A on the Mayo Clinic web site, relating to how lack of sleep can make your immune system weaker.
Dr. Timothy Morgenthaler gives this answer to a visitor question:
During sleep, your immune system releases proteins called cytokines. These substances increase in the presence of an infection, inflammation and stress. Increased cytokines are necessary in fighting infection and regulating deeper sleep. In addition, other infection-fighting cells are reduced during periods of sleep deprivation. So, your body needs sleep to fight infectious diseases.
Dr. Morgenthaler cautions that more sleep is not always better, as it can lead to weight gain, heart problems, stroke, sleep disorders, depression and other health concerns.
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