Immune System Stronger During Sleep

We all know that we tend to sleep more when we're sick - having just got over a bad dose of 'flu I can personally confirm that! Now scientists have confirmed what many have long suspected: the immune system is more active during sleep. At least it is in fruit flies, and the scientists seem to think that this suggests the same will be true of humans.

Researchers at Stanford University infected fruit flies (Drosophila melanogaster) with bacteria at different times of the day. The results, reported to the American Society for Cell Biology (ASCB), showed that those infected when asleep fought the bacteria better and were more likely to survive.

According to Mimi Shirasu-Hiza of Stanford University:

"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"

Er, yes, just what I was about to say...