Home » WHAT WILL HAPPEN IF » What would happen if a human did not sleep at all?

What would happen if a human did not sleep at all?

If a human did not sleep at all ? You might experience something like the following:

24 hours — Mild delirium, mood swings and periods of intense sleepiness or activity
48 hours — Impaired coordination, hormonal changes and decreased general memory function, but improved short-term memory (according to at least one study)
72 hours — Visual hallucinations and unintentional periods of “microsleep” (a few seconds to a minute of blacking out)
100+ hours — Re-enactment of Fight Club
11+ days — Win the prize for longest period a human has voluntarily gone without sleep (current holder is one Randy Gardner)
2+ weeks — Some chance of death. Experiments with rats showed that they died after 2-4 weeks of researchers keeping them awake in an experimental setting, probably from hypermetabolism
6+ months — Certain death; staying awake this long is only associated with rare disorders like Fatal familial insomnia

An interesting detail is that studies of various humans and animals going for long periods without sleep don’t show significant short or long term health effects — when you eventually do die from lack of sleep, it’s probably not from a nasty cold that got out of control.

Anecdotally, not getting enough sleep (as opposed to getting none at all) does significantly increase your chance of getting sick, but I don’t see any research on that. Perhaps the sickness thing is related to stress.

A recent discovery pretty much explains everything, including why all animals with real brains must sleep:

There is something called the blood-brain barrier in the blood vessels of the brain that makes it much harder for many chemicals to pass through.

The recent discovery is that this barrier opens up somewhat during deep sleep. The purpose and implications of this should be obvious:

A) The brain must be protected from the chemical abuse of letting waste products from the rest of the body into the brain.

B) The waste products of brain metabolism must be let out at some point.

C) This should only happen when the rest of the body is running a very low metabolism long enough for the kidneys to clean up the blood.

Therefore: Sleep is VERY important for the health of the brain. Oh, gee, by the way, memory consolidation happens at that time, but that probably evolved after the need for sleep was well established.

Curiously, migrating birds like ducks and geese can sleep with half of their brain at a time while migrating for long periods of intense exercise. This questions what I wrote above. But migrating birds are not remotely as intelligent as say felines or primates, or even birds of prey. Perhaps there is a reason for this.

Leave a Reply