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Insomnia - What it is

Insomnia Conditions and Treatments

Insomnia is the complaint of inadequate or poor quality sleep that interferes with normal daytime functioning.

For some people, insomnia means difficulty in falling asleep or waking up frequently during the night with problems getting back to sleep. For others, it is waking up too early in the morning and/or experiencing unrefreshing sleep. It can be transient or chronic.

Everyone has a rough night or two, or short-term (transient) insomnia. Chronic insomnia, though, lasts for more than a month.

You should consider seeking medical advice if your sleep has been disturbed at least several times over the past month, has gone on for weeks and months, or if it interferes with the way you feel or function during the day.

Introduction to insomnia

Sleep is essential for health providing rest and restoration for the mind and body. It is the regular period in every 24 hours when we are unconscious and unaware of our surroundings. There are two main types of sleep:

  • Non-REM sleep
    The brain is quiet, but the body may move around. Hormones are released into the bloodstream and our body repairs itself after the wear and tear of the day.
  • Rapid Eye Movement (REM) sleep
    It comes and goes throughout the night and makes up about onefifth of our sleep time. During REM sleep, our brain is very active, our muscles are very relaxed, our eyes move quickly from side to side and we dream.

We move between REM and non-REM sleep about five times throughout the night, dreaming more as we get towards the morning.

During a normal night, we will also have short periods of waking. These last one or two minutes and happen every two hours or so. We are not usually aware of them. We are more likely to remember them if we feel anxious or if there is something else going on - noises outside, our partner snoring etc.

How much sleep do we need?

There is no ‘normal’ amount of sleep; more importantly, it is how well you sleep, not how long your sleep is. Sleep requirements change during the course of a lifetime.

  • Babies sleep for about 17 hours a day.
  • Older children require nine or 10 hours per day.
  • Most middle-aged people function best on seven to nine hours of sleep, though some do well with as little as four hours, while others need up to 11 hours.

Older people need the same amount of sleep, but will often only have one period of deep sleep during the night - usually in the first three or four hours, after which they wake more easily.

We also tend to dream less as we get older. Older people also often find that their sleep at night is broken, particularly if they take naps during the daytime.

What if I do not sleep?

The occasional night without sleep will make you feel tired the next day, but it will not harm your physical or mental health.

However, after several sleepless nights, you will start to find that:

  • You are tired all the time
  • You drop off to sleep during the day
  • You find it difficult to concentrate
  • You find it hard to make decisions
  • You start to feel depressed

This can be very dangerous if you are driving or operating heavy machinery. A lack of sleep may also make us more vulnerable to high blood pressure, obesity and diabetes.

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The information provided is not intended as medical advice. Terms of use. Information provided by SingHealth