What is insomnia and how much sleep do we need?

Sleeping trouble is the most widely reported psychological disorder in the UK, affecting a third of the population.

Check out our 10 tips to beat insomnia

Insomnia is defined as difficulty getting to sleep, difficulty staying asleep or having non-refreshing sleep.

Having insomnia means that these difficulties happen three or more times a week, persist for at least a month and can affect our ability to function properly during the day.

Persistent insomnia can affect personal lives and performance at work, and delay recovery after your illness. It's also a major cause of depression.

Symptoms can include:

  • lying awake for a long time before falling asleep
  • waking up several times in the middle of the night
  • waking up early and not being able to get back to sleep
  • feeling tired and unrefreshed by sleep
  • inability to concentrate during the day
  • irritability due to lack of sleep

Most people with insomnia report having low energy during the daytime, but few of them feel sleepy, says Professor Kevin Morgan of Loughborough University's Sleep Research Centre.

“Instead, they stay in a wakened state, feeling tired, lethargic and without vitality,” he says.

How much sleep do we need?

Most adults need between six and nine hours of sleep each night. Some people can feel perfectly rested with a lower amount.

Newborn babies can sleep for 16 hours a day, while school age children need an average of 10 hours. Most people over the age of 70 tend to be light sleepers and need less than six hours a night.

So how much sleep do we need? “Simply put, you need enough to make you refreshed and able to function efficiently the next day,” says Professor Morgan. The number of hours depends completely on the individual.

Insomnia is more common among older people, and among women. Gender differences can probably be explained by differences in lifestyle, hormones, and perhaps the fact that fewer men report these problems. 

“Factors such as periods, the menopause, pregnancy and child rearing can all contribute to insomnia,” says Professor Morgan.

If you need help with your sleep, read sleeping pills and the alternatives for information on the different types of insomnia treatment.

Page last reviewed: 17/07/2014

Next review due: 17/07/2016


How helpful is this page?

Average rating

Based on 79 ratings

All ratings

Add your rating

Want to find out how healthy you are?

Take our quiz to see how you score

Moodzone: sleep problems

Dr Chris Williams explains what you can do to give yourself the best chance of a good night's sleep. This podcast is one of an eight-part series for Moodzone

Why lack of sleep is bad for your health

Sleep deprivation can have profound consequences for your mental and physical health

Sleep tips for teenagers

Follow these practical hints and tips if your teenager has sleep problems.

Ditch the sleeping pills

Millions of sleeping pills are taken every year but non-drug treatments offer the best hope for tackling insomnia

Sleep problems in young children

How to deal with sleep problems in young children, including frequent waking and nightmares

Five steps to mental wellbeing

Feel happier with these five evidence-based steps to improving your mental wellbeing