Stanford University has done research on the effect a good night’s sleep has on a sick body. The research, involving fruit flies, reveals that the immune system fights invading bacteria the hardest at night.
“These results suggest that immunity is stronger at night, consistent with the hypothesis that circadian proteins upregulate restorative functions such as specific immune responses during sleep, when animals are not engaged in metabolically costly activities,” Stanford researcher Mimi Shirasu-Hiza said in a news release issued by the conference organizers.
The circadian rhythm runs the internal clock’s time for eating and rest every day, and it paces both the human body and the fruit fly. The researchers found, through previous experiments, that bacterial infection threw off the fruit flies circadian rhythm. This made them susceptible to infection.
This time around, they infected the flies with two different types of bacteria, at different times of day or night. The flies infected during the day were less likely to survive than those infected during the night. Low “phagocytic” activity – the body’s innate immune response – was detected in flies with a corrupt circadian clock.
SOURCE: American Society for Cell Biology, news release, Dec. 14, 2008