the folly I lack

I know you need sleep to have a strong immune system. I know from experience: almost all my colds start during Debate season, primed by the late-Friday-night-early-Saturday-morning turnaround.

But I am not this foolish:

For 14 days, the researchers monitored and recorded the sleep time of 153 healthy men and women ages 21 to 55. They also scored their sleep efficiency, the percentage of time in bed spent asleep.

Then they dripped a solution containing a rhinovirus into their noses and monitored their health for five days. Almost all subjects became infected, and more than a third had cold symptoms.

Did it really take a study to prove this one?