What is jet lag? Can we cure it? And why is it a big problem for astronauts who might one day live on Mars?
Common symptoms of jet lag include feeling bloated, sleepy and irritable. Here, Kate dives into the science of circadian rhythms, and armed with the facts, sets out to find a cure.
The term jet lag was first coined by Los Angeles journalist Horace Sutton in 1966. He said that jets travel so fast that they leave your body rhythms behind. That was actually pretty close to the truth.
Human bodies, says Kate, are governed by carcadian clocks. These clocks keep our internal systems in an almost exact 24-hour repeated pattern - so we know when to get up and go to bed.
If one was to take a flight to LA from London, our bodies would in effect be eight hours behind, because of the time difference. So we would feel tired during the day. But there's more to it than that.
Photosensitive ganglion cells in our eyes detect how light it is and lets our carcadian clock know if it's day or night. Our brains then begin secreting a sleep hormone called melatonin, depending on the light information.
How can we use this information to counter the effects of jet lag?
It's pretty simple: you need to readjust your bodies internal clock before you travel. In the days leading up to your holiday, gradually adjust your bedtime to get in sink with the time difference of your destination.
Easier said that done if you're an astronaut, however.
Future human colonists on Mars are going to take some time to adapt because at 24.6 hours, a day on Mars is just longer enough than that of Earth's to knock their bodies off kilter.