A study says that going to bed late may be bad for us. It could shorten our life. The study was done in the UK. Researchers spent six-and-a-half years looking at 430,000 adults between the ages of 38 and 73. The researchers compared the deaths of people who went to bed early to those who went to bed late. Night owls (people who go to bed late) were 10 per cent more likely to die during the period of the study. The researchers said that night owls were at a higher risk of poor health or an early death compared to early birds (people who sleep and wake up early).

The researchers said working hours should change to reduce the risks for night owls. A researcher said: "This is a public health issue that can no longer be ignored." He said night owls should start and finish work later in the day so they could sleep longer in the morning. He said night owls were more likely to suffer from mental problems, diabetes, and breathing problems. They were also more likely to smoke, drink alcohol and take drugs. Researchers also said different sleeping patterns at weekends could increase the chances of health problems for night owls.