Immunity and Sleep

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Sleep and the immune healthy immune system function have been connected to one another since man realized he had to sleep when tired and that sleep was necessary. Aristotle addressed the issue of sleep in his essay "On Sleep and Sleeplessness," in which he wrote that sleep and waking originate in the heart and are regulated by a primary sense organ. He proposed that after food is eaten, evaporation from it rises to the brain, condenses, and sinks down to the heart, causing sleep. (1).

The connection between the two is extant and can be characterized by early sleep deprivation experiments on dogs by a "progressive exhaustion of psychic activity." Giulio Tarozzi in 1899 investigated the metabolic effects of sleep deprivation in four sleep-deprived dogs (one of which was starved), and found that elimination of nitrous compounds increased late in the deprivation period and was accompanied by hyperthermia; the body temperature then declined prior to death. (2)

This was an early study and although showed some negative physiological impact the effect on immune function is actually an ongoing debate. One must consider the following excerpt regarding immune system and sleep deprivation:

"... host immune systems in higher organisms are complex and multilayered, and involve relatively fixed, anatomical barriers (such as skin, mucosal surfaces, secretions, and cilia) as well as active components; the latter include nonspecific and specific defenses, which are further subdivided into cellular and humeral components. Given this complexity, studies examining the connection between immunity and sleep have been limited for several reasons. First, host defenses to pathogens usually involve interactions among multiple cellular and humeral components acting locally and systemically. While local coordination is achieved through direct cell-to-cell interactions and through soluble factors and cytokines, systemic coordination involves the neuroendocrine ...