12 Scientific Facts You (Probably) Didn’t Know About Sleep

How nature’s weirdest biological feature shapes your body and mind

Commercially licensed by Alex Garcia via Flickr

11 years. That’s how much older men effectively become when they restrict themselves to 5 hours of sleep, in terms of testosterone levels.

In an evolutionary sense, laying unconscious for 8 hours a day must have been a disadvantage. Exposed to predators, not hunting or gathering — what’s the use in that? Neuroscientist Matthew Walker argues that the absurdity of sleep just shows how crucial it must be to our health:

“When you think about sleep as a state, it makes no sense. […] It’s almost idiotic. If sleep does not serve an absolutely vital function, it’s the biggest mistake the evolutionary process ever made.”

After a short investigation, I can safely conclude that he is right.

1. Vaccines are half as effective for sleep-deprived people.

In this experiment, a test group of subjects were restricted to 4 hours of sleep per night for 6 days. Then, they received 7 days of 12-hour recovery sleep, after which both the test group and the control…