But now science is beginning to show that getting the right amount of sleep might be the key to making the rest of our lives run more smoothly.
Increasingly, research is indicating that the quality and quantity of our sleep affects every part of our lives, from success in work and school to our likelihood of developing problems such as obesity or mental illness.
Writing in the journal Frontiers in Neurology last year, American researchers highlighted the growing body of research confirming that students who have insomnia, inadequate sleep, daytime sleepiness, irregular sleep patterns or poor sleep quality do not perform as well in school as others.
Big impact ... Research indicates that the quality and quantity of our sleep can affect every part of our lives.
Many sleep researchers now advocate the introduction of staggered start times for older high-school students - one of the most under-slept groups in society after shift workers.
But the most cutting edge of sleep research is beginning to show it seems also to be linked to mental illness.
Nicholas Glozier is at the forefront of such research in his work as a professor of psychiatry and sleep research at the Brain and Mind Research Institute at the University of Sydney.
He says lack of sleep is one of the most common problems for which people seek help from GPs, with about one-third of women and one-quarter of men saying they have trouble falling or staying asleep.
The average Australian sleeps for about 8¼ hours a day - much less than that and you may not be getting enough. The average sleep period for a teenager is about seven hours. People who get six hours or less a night are at risk of illnesses such as bipolar disorder, anxiety and panic disorder.
Professor Glozier published research late last year that followed 20,000 people aged 17 to 24 for a year. It found those who slept less than five hours a night were three times more likely than normal sleepers to become psychologically distressed.
A big question for researchers is whether sleep deprivation is a cause or effect of mental illness.
"One of the real issues with sleep research at the moment is it is a bit like where psychiatry was 15 years ago," he says. "We really don't know whether [improving sleep] is going to impact on other health outcomes."
In the next 15 years - provided research is well funded by governments and universities - Glozier says we will be on our way to finding some of the answers.
One researcher who has conducted an Australian-first trial into sleep and teenagers is Amanda Gamble, a psychologist and research fellow with the Woolcock Institute of Medical Research.
For many of the teenagers Dr Gamble sees, sleep has become a stressful part of life. It causes fights with parents and absences from school. One patient's parents were so desperate, they would spray their child with water in the mornings to force them up.
"For most of these teenagers, falling asleep and staying asleep has made them feel incredibly out of control and it's quite a frightening thing," she says. "If you can't control a basic bodily process that happens every single day, there's no escaping it."
But there is light at the end of the tunnel. Her research, unpublished, has shown that through a four-session program using cognitive behavioural therapy, not only were patients getting to sleep earlier and sleeping longer, they also became less depressed and anxious. She is recruiting teenagers for a larger version of the study.
For some, sleep is as simple as rolling into bed and snoring within minutes. But those who lie awake for hours can attest to the way sleep deprivation can creep into every crevice of life. But now science is catching up and beginning to reveal the intricate connections between how we sleep and how we live.
INSOMNIA CAUSES:
Medical
- Obstructive sleep apnoea
- Narcolepsy
- Drug or alcohol addiction
- Restless legs syndrome
- Depression and anxiety disorders
- Neurological conditions — dementia, Parkinson's
- Hormone changes — menstruation, menopause
Behavioural or social
- Increased working hours
- Shift work
- Major life event — divorce, bereavement, job loss
- Jet lag
- Poor "sleep hygiene" — irregular sleeping times, caffeine before bed, inadequate exercise