We don’t usually need to think very much about sleep. It’s routine. Even so, most of us sometimes just can’t sleep properly. We call it insomnia. It’s usually just for a short time, perhaps when we’re worried or excited. When things settle down, we start sleeping properly again. If you can’t sleep properly, it can be a real problem because we all need sleep to keep healthy.
When you sleep, you become unconscious and unaware of what’s going on around you. As you sleep, you pass through different stages – and there are two main types:
This comes and goes throughout the night, and makes up about one fifth of your sleep. The brain is very active, eyes move quickly from side to side and you dream. Although your brain is active, your muscles are very relaxed.
Your brain is quiet, but your body moves around while you sleep. Hormones are released into the bloodstream and your body repairs itself after the wear and tear of the day. There are 3 stages of non-REM sleep:
You move between REM and non-REM sleep about 5 times during the night, dreaming more towards the morning.
On a normal night, most people wake up for one or two minutes every 2 hours or so. You aren’t usually aware of these ‘mini wakes’, but may remember them if you feel anxious or there is something else going on – noises outside, a partner snoring etc.
This mainly depends on your age.
There are differences between people of the same age. Most will need 8 hours a night, but some (a few) people can get by with only 3 hours a night.
The short periods of being awake can feel much longer than they really are. So you can feel that you are not sleeping as much as you really are.
An occasional night without sleep will make you feel tired the next day, but it won’t affect your health.
However, after several sleepless nights, you will start to find that you:
This can be very dangerous if you are driving or operating heavy machinery. Many deaths are caused each year by people falling asleep at the wheel while driving.
If it continues, lack of sleep can make you more likely to get: