PASSENGERS are guilty of making a number of mistakes while flying that could have a bad effect on their bodies.
The dry air, the altitude and sitting still for a long time all take their toll on passengers, but a lot of people don't take any measures to minimise the impact.
But that could lead to problems ranging from dehydration to deep vein thrombosis (DVT), if you're not careful.
That's why passengers are being urged to take steps in order to make sure they get off the plane in the same condition as they were in when they boarded it.
Firstly, most passengers are guilty of not drinking enough water, according to Stuff.co.nz.
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They claim that not drinking enough is the reason people have dry noses, throats and skin during flights.
They also say that the longer the flight, the greater the risk of dehydration.
To combat this, the recommendation is to drink water before and during the journey.
This advice is pretty much universally backed up by flight attendants, with one saying you could need as many as 13 glasses of water on a flight between the UK and Florida.
The crew member, who works for Air France, said they are told how much to drink to avoid getting jet lag.
She told travel money specialist Equals: "As a flight attendant, the medical staff tell us we have to drink one litre of water for every four hours of flying."
She added: "I would definitely tell passengers to drink lots of water."
For a long-haul flight, this could mean drinking much more than you may realise.
For example, a flight from the UK to Florida can take up to 12 hours, meaning three litres of water should be drunk during the flight.
This works out to nearly 13 glasses to prevent the effects of jet lag - almost double the recommended daily advice when on the ground.
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Passengers should also give booze and coffee a swerve while flying, as they can have the opposite effect of water and make dehydration even worse.
As well as dehydration, DVT is also a serious consideration for people, particularly of a certain age or weight.
This occurs when you get a blood clot (a sticky mass of blood cells) in a vein that is deep below the skin.
DVT usually occurs in the leg and tends to affect thick veins that run through the muscles of the calf or the thigh.
It can be caused by sitting in the same position for too long, which is why passengers are urged to walk around the plane, or do small exercises with their feet to keep the blood moving.
Emirates flight attendant Lauren Guilfoyle recommends using the "alphabet technique" while sitting in your seat to increase movement.
She spoke to Reader's Digest to explain how the technique worked.
She said: "Motion each letter of the alphabet with your foot to get the blood flowing and avoid ankle swelling.
"[These] circulatory exercises will keep your cheeks looking rosy and make you look more awake when you step off the plane."
Other passengers swear by compression socks as well, which also aid the flow of blood while sitting still in the air.
The socks apply gentle pressure to the muscles in the lower legs, increasing blood flow and reducing the chances of DVT, oedemas and other problems.
Meanwhile, wearing tight clothes on planes can increase your chances of getting DVT.
And your choice of seat can affect whether or not you feel unwell during a flight.
