Why a long night's sleep may be bad for you

Many of us try, but often fail, to get eight hours' sleep each night. This is widely assumed to be the ideal amount - but some experts now say it's too much, and may actually be unhealthy.

We all know that getting too little sleep is bad. You feel tired, you may be irritable, and it can contribute to obesity, high blood pressure, diabetes, and heart disease, doctors say. But too much sleep? You don't often hear people complaining about it.

However, research carried out over the past 10 years appears to show that adults who usually sleep for less than six hours or more than eight, are at risk of dying earlier than those sleep for between six and eight hours.


To put it more scientifically, there is a gradual increase in mortality risk for those who fall outside the six-to-eight-hour band.

Prof Franco Cappuccio, professor of cardiovascular medicine and epidemiology at the University of Warwick, has analysed 16 studies, in which overall more than a million people were asked about their sleeping habits and then followed up over time.

Cappuccio put the people involved into three broad groups:
• those who said they slept less than six hours a night
• those who said they slept for between six and eight hours
• those who said they slept for more than eight hours  See More