Scientists have warned that shift work can prematurely age and dull the brain’s intellectual ability.

A study, published in the journal Occupational and Environmental Medicine, found that working anti-social hours for ten years aged the brain by six and a half years.

Dr Philip Tucker, part of the research team in Swansea, told the BBC: "It was quite a substantial decline in brain function, it is likely that when people trying to undertake complex cognitive tasks then they might make more mistakes and slip-ups, maybe one in 100 makes a mistake with a very large consequence, but it's hard to say how big a difference it would make in day-to-day life."