Research led by the University of Adelaide's Professor Robert Adams for the Sleep Health Foundation has found 33 to 45% of adults sleep either poorly or not long enough most nights, leaving them to face the new day with fatigue, irritability and other side effects of sleep deprivation.

The work, published in the journal Sleep Health, also shows alarmingly high rates of internet use just before bed, particularly among women, and carries admissions from one in five people that they've nodded off while driving.

The University's Professor Adams (Adelaide Medical School) led the online study of more than 1000 Australians. It found sleep problems, such as difficulties sleeping at least a few times a week or more, or sleep–related daytime symptoms, are very common, affecting more than a third of adults. Women are significantly more likely than men to have difficulty falling asleep, waking too early, feeling unrefreshed, sleepy, fatigued, exhausted, irritable and moody, even when they sleep as much as men.

Diagnosed sleep disorders are common, with men more likely to suffer from the night time breathing condition obstructive sleep apnoea and women hardest hit by insomnia.

The Foundation says it was also alarmed by figures showing 29% of adults drive while drowsy at least once a month, and 20% have nodded off at the wheel at some time. 5% admitted having an accident in the past year because they dozed off. The work day is also affected, with some 21% of men and 13% of women questioned admitting to having fallen asleep at work in the past month.

A comparison with the Foundation's 2010 survey suggests sleep problems and their consequences are 5 to 10% worse than they were six years ago.

The result is a less productive, less safe and less pleasant work and family environment, Dr Hillman explains.

While individuals can make lifestyle changes to help get a better night's sleep, the problem was now so widespread and insidious, a national health strategy was needed to turn trends around, the foundation says. "We need a fundamental change in the way sleep is viewed by everyone from teenagers, parents and teachers through to bosses, doctors and our top politicians," Dr Hillman says.

Key Findings:

• Inadequate sleep, of either duration or quality, and its daytime consequences regularly affect 33–45% of adults.
• Average reported sleep time is 7 hours, although 12% sleep less than 5.5 hours and 8% over 9 hours.
• Three–quarters of those who sleep less than 5.5 hours report frequent daytime impairment or sleep–related symptoms.
• Frequent, loud snoring is reported by 24% of men and 17% of women. Among these, 70% report daytime impairment or other sleep–related symptoms.
• Almost a third of adults (29%) report making errors at work due to sleepiness or sleep problems within 3 months of the survey.
• Almost a third of adults drive when drowsy at least every month, and one in five have nodded off while driving within the last year.
• 44% of adults (47% women, 40% men) are on the internet just before bed almost every night. Of these, 59% have two or more sleep problems.