This is how much water you actually lose during a flight

This will make you re-think ordering anything other than water on a plane...

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This will make you re-think ordering anything other than water on a plane...

Think about it. Long-haul flights are a digital detox dream. You just have to sit there, watch movies, enjoy being fed on cue and you're able to take naps whenever you feel like it.

Sadly though, flights aren't quite as relaxing on your body. We already know you end up eating a lot of calories from plane food and according to rehydration supplement brand Phizz's Physiotherapist & Head of Phizz Sport, Yasmin Badiani, long-haul flights can take a considerable toll on you physically, too.

Spending a long period of time confined in a reduced oxygen environment with low humidity seriously dehydrates you...

'Dehydration is a major issue when travelling by airplane,' Yasmin tells us. 'The problem arises due to spending long periods of time in a climate-controlled environment where the relative humidity can be as low as 10-15%, which is three times drier than the Sahara desert!'

'In an average 10 hour flight, men can lose approximately two litres of water and women around 1.6 litres. This means that on a London to Sydney flight a passenger could lose up to 4 litres and 8% of their bodily water.'

And since research shows that spending six hours in a climate simulator that mimics conditions on a plane, leads to a significant decrease in hydration status, with around 2% loss in total body water content over this time, despite them drinking 400ml of water, it's safe to say, flying is bad for hydration levels.

'Around 50% of this decrease is due to ‘insensible water loss’, mostly due to respiration. Insensible water loss is due to a combination of the mildly hypoxic environment which increases breathing rate and the dry cabin air and is difficult to prevent or reduce this type of water loss.'

'A 1-2% decrease in hydration has significant impact on the health and mood of passengers and can affect cognition, attention, memory and critical thinking, as well as leading to feelings of tiredness, fatigue and irritability.'

Oh, and if that's not enough, because your mucosal membranes become dehydrated while flying, their ability to trap bacteria or viruses becomes less efficient and effective so you're more likely to catch an illness.

Pass us the big bottles of water, we say!

Delphine Chui