Children who have had the old maxim chanted at them to justify an early bedtime will rejoice in a survey of 1,200 over 65-year-olds, which found night owls are more likely to have a bigger income and a car thanvirtuous larks who are in bed by 11 and up before eight.
In research that is published in today's BMJ, the scientists looked at a Department of Health and Social Security survey in which data on sleeping patterns, health and socio-economic circumstances had been recorded. Just under 30 per cent of the group were "larks" (to bed before 11pm and up before 8am) and 26 per cent "owls" (to bed after 11pm and not up till 8am or after).
Famous larks have included Thomas Edison, who believed too much sleep was bad for the health and, appropriately enough, invented the lightbulb.Samuel Johnson cautioned that "nobody who does not rise early will ever do any good," although the force of his advice was rather diminished by his admission that he invariably lay in bed until noon.
The researchers found that owls had larger mean incomes and were more likely to have access to a car. "There was no indication that larks were richer than those with other sleeping patterns." said the scientists. More than 40 per cent of owls had access to a car compared with 34 per cent of larks. Owls were also more likely to have a good standard of accommodation and to come from a non-manual social class.
There was no evidence that health differed for larks, either self-reported or after assessment by a geriatrician. Mortality from all causes was lower in the cases of larks and owls than in other groups, but was broadly similar for both groups.
In fact the scientists said the best way to cut the risk of early death was not to linger between the sheets. Those who spent longer than eight hours in bed a night had an increased risk of death, and while it was unlikely to simply reflect the fact that the sick spend longer in bed, the underlying biological mechanism was not known.
"We found no evidence ... that going to bed and getting up early was associated with any health, socio-economic or cognitive advantage," the scientists said. "If anything, owls were wealthier than larks, though there was no difference in their health or wisdom."