Party lovers and workaholics who stay up late and rise early are putting their health at risk, researchers have found. People who regularly sleep less than six hours a night, or whose sleep is disturbed, have a 48 per cent greater chance of developing or dying from heart disease and a 15 per cent higher chance of a stroke.
The findings are based on studies of 470,000 people in eight countries – including the UK, the United States, Sweden and Japan – who were tracked for between seven and 25 years. Professor Francesco Cappuccio, of Warwick Medical School, who led the study published in the European Heart Journal, said: "The trend for late nights and early mornings is a ticking time bomb for our health. The work/life balance struggle is causing too many of us to trade in precious sleeping time.
"We looked at the duration and quality of sleep. If you have difficulty falling asleep or you wake up in the night, that will affect the quality of your sleep.
"We found a window of between six and eight hours' sleep a night when we were unable to pick up any adverse events. When you go below that, you have significant nasty effects."