Everyone knows that getting too little sleep can be bad for your health, but new research suggests having a regular lie in could be even worse.

Too little sleep and too much shut eye both increase the risk of serious illnesses including diabetes, new research suggests.

A study of more than 50,000 people found those who get too much or too little sleep are more likely to develop a range of physical and psychological conditions including coronary heart disease, diabetes, anxiety and obesity.

People who struggle to sleep for more than six hours a night are at greater risk of coronary heart disease, stroke, diabetes, obesity and mental illness.

On the other hand, scientists claim lots of rest is not necessarily good for health either.

Sleeping for too long carries the same risks as reduced sleep, although the American Academy of Sleep Medicine study found the risk of coronary heart disease, stroke and diabetes was even higher among people who sleep for a long time.

Getting the ‘optimum’ amount of sleep each night reduces the risk of developing the diseases and can help those who already suffer with health problems common among the over 45s.

Sleep expert Dr Safwan Badr said: ‘A healthy, balanced lifestyle is not limited to diet and fitness - when and how you sleep is just as important as what you eat or how you exercise.

‘It's critical that adults aim for seven to nine hours of sleep each night to receive the health benefits of sleep, but this is especially true for those battling a chronic condition.

‘Common sleep illnesses - including sleep apnoea and insomnia - occur frequently in people with a chronic disease and can hinder your ability to sleep soundly.

‘So if you're waking up exhausted, speak with a sleep physician to see if there's a problem.

‘If you are diagnosed with a sleep illness, treating it could significantly improve disease symptoms and your quality of life.’

Dr Badr and colleagues analysed health records of 54,000 Americans over the age of 45 for the study published in the journal Sleep.

They found almost a third were classed as ‘short’ sleepers, who said they got six hours or less sleep a night.

Two thirds were classed as ‘optimal’ sleepers who had between seven and nine hours in a 24 hour period, while a small number said they were ‘long’ sleepers - they slept for more than ten hours a day.

They say it shows sleep patterns are associated with psychological, as well as physiological illnesses, the symptoms of which could be alleviated by getting the correct amount of rest each night.

Chronic disease expert Dr Janet Croft at the U.S. Centres for Disease Control and Prevention said: ‘Some of the relationships between unhealthy sleep durations and chronic diseases were partially explained by frequent mental distress and obesity.

’This suggests that physicians should consider monitoring mental health and body weight in addition to sleep health for patients with chronic diseases.’