Completed Studies

Sleep Deprivation in Humans, Transient Immunodepression
and Provision of Amino Acids


Increasing evidence suggests that sleep is important for proper function of the immune system. Sleep deprivation may lead to depression of the immune system and impaired health. However, the effects of sleep deprivation on some aspects of immune cell function require more investigation.


The first experiment of this study is designed to determine if the loss of one night's sleep leads to a temporary depression of the immune system. If this temporary immune system depression does occur, can it be moderated by a night of normal sleep? If the depression cannot be moderated by sleep alone, then a second experiment will be used to determine whether the consumption of the amino acid glutamine may restore or enhance cellular function in the immune system.


Experiment 1: A group of 12 male volunteers was paid $10 per hour for 23 hours of participation. Study measures included blood draws, performance testing, and questionnaires across four mornings. In addition, the performance tests and questionnaires were repeated hourly across a single night of sleep deprivation. The experiment consisted of a 3-hour training period, three morning testing sessions of two hours each, and one overnight and morning testing session of 14 hours for a total of 23 hours. Participants were present in the research facility for blood draws and testing from 6:30 a.m. to 8 a.m. on Monday, Tuesday, Thursday, and Friday mornings. Participants were also present from 6 p.m. Tuesday evening to 8 a.m. Wednesday morning for the night of sleep deprivation.

Experiment 2: This experiment was designed to repeat Experiment 1 on 16 male volunteers with the additional component of administering daily oral doses of glutamine or a placebo. The participant schedule was the same as that in Experiment 1.