What happens when I don’t sleep enough and how will I feel if I don’t sleep enough? Let's dive into what really happens when you don't prioritise sleep...

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What happens when I don’t sleep enough?

A lot will happen to you if you don’t sleep.  Or rather, a lot doesn’t happen to you. Here are four things worth thinking about;

  1. You won’t learn.  During sleep new information you’ve learned that day is moved from its temporary store, the hippocampus, into your long term memory in the neocortex.  No sleep, no sorting new information and no emptying the hippocampus. No room for learning anything the next day.
  1. You won’t create.  During REM sleep your brain takes pieces of information and memories and randomly joins them together to develop new thinking.  No sleep means next to no new thinking or being creative.
  1. You won’t clean your brain.  During NREM sleep some cells in your brain shrink.  This creates space in the brain and lets the cerebrospinal fluid flush out the toxins and metabolic waste of the day.  No sleep and you’ll have a brain full of toxins. Some of which are linked to Alzheimer’s.
  1. You won’t repair muscle and grow new tissue.  During NREM sleep your body breaks down or repairs old and damaged cells and builds new cells. No sleep and no cellular recovery or muscle growth.

How will I feel if I don’t sleep enough?

Losing sleep is like pouring treacle into a machine.  You’ll get a bit slower, think less clearly and have less energy.

After a few hours of sleep loss for a few nights your movements will be impaired and your reaction times will slow.  Your ability to learn and think clearly will decrease. You will feel fatigued and start craving sleep.

A few more nights and you start to get slow and confused.  You will struggle to perform tasks that need any kind of concentration and calculating.  You’ll start to get irritated and impolite.

If you keep going you will start to experience microsleeps.  You will start to experience illusions, hallucinations, irritation, inaccuracy and sensations of pressure around the head.

You’ll eventually experience disturbances in reasoning and start to suffer extreme fatigue, distrust and delusions. Intellectual and problem-solving go right out of the window.

If you experience significant sleep deprivation, perhaps 5 – 7 days of total sleep loss, you will experience depersonalisation and be no longer capable of interpreting reality. You’ve hit full sleep deprivation psychosis.  Otherwise known as madness.

For more on sleep deprivation check out our Sleep Problems page for more detailed blogs on the effects of not prioritising sleep.

Written by
Sam Billington

Sam is our sleep guru. I am fascinated by sleep and I've used my science training to research and learn about sleep. I have been providing sleep advice and personal sleep plans for years. My day job is Head of Workplace Culture in Defra, I live in London with my wife and have a PhD in Ecology and Biology.