Sunshine to meal times: How to beat jet lag

Many will have experienced it – that feeling at 3pm when all you want to do is go to bed and sleep like a log.

Or, finding yourself wide awake at 3am, brain whirring and no prospect of sleep.

Jet lag - the world's most annoying holiday souvenir – is the price we pay for flying off around the globe on travels or holidays.

Jet lag is what you feel when local time changes abruptly, but your body clock is playing catch up, says Dr Nina Rzechorzek, who leads research at the University of Cambridge on human brain temperature, sleep, and circadian rhythms.

"After rapid travel across several time zones, your internal biological time initially stays aligned with home while you are trying to sleep, eat, and function on destination time.

"That mismatch can cause disturbed sleep, daytime sleepiness, poor concentration, irritability, reduced performance, and digestive problems," she says.

And jet lag is closely linked to what are called our circadian rhythms – the body's internal body clock.

"Almost all the cells in our body maintain their own 24-hour clock, which are synchronised by a master clock in the brain," explains Dr Anna Edmondson, of the Laboratory of Molecular Biology at the University of Cambridge.