Expert's 'life-threatening' warning to people getting less than seven hours sleep

A recent study by Chinese researchers highlighted the benefits of enjoying even a short weekend lie-in that could help a person reduce the risk of developing a deadly condition

A common 'myth' over the ideal number of hours sleep each night that people should be aiming for has been debunked by researchers.

People often believe that getting at least eight hours sleep is needed in order to maintain a healthy balance in the body. Now, a study presented by China's National Centre for Cardiovascular Disease at a European Society of Cardiology meeting claimed that a person typically needs between seven to nine hours of sleep every night. Loughborough University's Emeritus Professor Kevin Morgan noted that these results challenge the eight-hour-a-night notion. "The latest study is yet another to explode the myth that we need exactly eight hours' sleep a night.

"If we have to put a number on it, most people need somewhere between seven and nine hours each night, but there are always outliers," he said when speaking to The Times. The academic also pointed out the study's findings over the health rewards of having a weekend lie-in. According to the study, the advantages of compensatory sleep, or sleeping longer at weekends, found that just 1.28 hours more in bed could be beneficial. While having more sleep was linked with a decreased risk of developing heart disease, reports the Express.

Lead author Yanjun Song said: "Sufficient compensatory sleep is linked to a lower risk of heart disease. The association becomes even more pronounced among individuals who regularly experience inadequate sleep on weekdays." Anyone who doesn't sleep for very long during the working week may experience the benefits of catching up over the weekend if they have the opportunity to, data from the study found. Sleep deprivation can affect more than just the body, however, and a survey of 2,000 revealed the everyday impact it has on them.

Almost 90% said they have felt 'tangry' - a blend of tired and angry - with sleep expert Dr Sophie Bostock explaining the problem: "Our sleep, well-being and behaviour are intimately linked. A lack of sleep can alter the emotional control centres of the brain, making us more sensitive to stress, and reducing self-control." She went on: "Some people become more impulsive and aggressive. This survey is also a valuable reminder that many of us can feel like a different person when we are sleep deprived and can lash out in ways we later regret."