If work worries regularly give you sleepless nights, you might not want to hear that new research has found an unequivocal link between a lack of sleep and early death.
Academics from University of Warwick in the UK and the Federico II University medical school in Naples, Italy, examined data from 16 studies carried out across the world over the past 25 years which between them covering more than 1.3m people and more than 100,000 deaths.
They found that sleeping consistently for less than six hours a night can cause an early death. In fact, those who generally slept for less than six hours a night were 12 per cent more likely to experience a premature death over a period of 25 years than those who consistently got six to eight hours' sleep.
But too much sleep could also point to problems and underlying ailments, the researchers found.
"Modern society has seen a gradual reduction in the average amount of sleep people take, and this pattern is more common amongst full-time workers, suggesting that it may be due to societal pressures for longer working hours and more shift-work," said the University of Warwick's Professor Francesco Cappuccio.
"On the other hand, the deterioration of our health status is often accompanied by an extension of our sleeping time.
"Consistently sleeping six to eight hours per night may be optimal for health. The duration of sleep should be regarded as an additional behavioural risk factor, or risk marker, influenced by the environment and possibly amenable to change through both education and counselling as well as through measures of public health aimed at favourable modifications of the physical and working environments."