Squashing into small seats, being unable to sleep comfortably and eating tasteless food are a few things we all dread when we fly. But our bodies can react to being in the air in some ways we don't even realise. Even buying a first-class ticket won't help.
Here are a few of the clever responses your body makes when you fly. Get to know them well so you can help manage your mid-air self on your next adventure away.
1. ACHES AND PAINS CAN GET WORSE
It isn't just the digestive system that responds to the air pressure change; fluid and gases within our circulatory system and joints can thicken, causing added pressure within the joints themselves.
For individuals who suffer from inflammatory joint pain like arthritis, don't be surprised if symptoms are exacerbated following a long haul flight. It may also be that joints that are a bit vulnerable, or even ones that have previously been, take a little longer to settle down after the flight. You may therefore experience swelling, but don't worry; it is just a clever protective mechanism the nerves and joint have going on.
2. YOU'RE MORE SUSCEPTIBLE TO COLDS
About half of the cabin air is re-circulated, meaning your immune system is continually exposed to any germs lurking around the plane. It is said that for this reason, you are 100 times more likely to catch a cold when you are flying. So, best to boost your immune system by eating healthily and taking regular exercise before you take to the air. Wash your hands regularly (or use a hand sanitiser) when you're on board.
3. IT MAKES YOU MORE THIRSTY...AND TIRED
Your body can lose up to 1.5 litres of water during a three-hour flight. Humidity can be as low as 4% and, with the re-circulated air, moisture in your skin can be sucked away pretty quickly. It can also dry up your mucus secreting glands in the mouth, nose and throat to give you that feeling of dryness and breath that isn't as fresh as when you left.
We're all familiar with the effects of dehydration; you feel tired, lose mental focus and can get muscle aches. A sluggish feeling can also be caused by the lower oxygen levels available at higher altitudes- similar to when you go skiing or mountain hiking. Cabins are pressurised to 75% of normal atmospheric pressure. Lower oxygen in the blood (called 'hypoxia') can leave us feeling dizzy, headachy, nauseous and fatigued.
Try to avoid alcohol when in the air as it won't help with your hydration. Making sure you drink plenty of water is key during the flight - just perhaps not the plane water itself - and you could try applying a good moisturiser to skin at regular intervals too.
4. YOU GET STIFFER THAN USUAL
Being sedentary for a longer period of time causes muscles and joints to stiffen up. It also is a reason why passengers often get swollen ankles and legs as it leads to blood pools, and in more serious cases, blood clotting; which is why you'll often see people wearing those stylish compression stockings.
Keeping yourself active during a flight is essential to help circulation. Flexing the ankles, moving the legs around regularly and even doing some stretching or 'plane-yoga' at the back of the cabin every hour is a good way to get the blood moving and can help with boosting oxygen levels too.
5. YOU LOSE SENSATIONS
A 2010 study revealed that you could lose 30% of your ability to taste sweetness and saltiness at high altitude due to the evaporation of nasal mucus, which causes the essential nerve for taste and smell to be affected too. About a third of your taste buds can become numb while you fly- handy considering the food served is far from Michelin star. You might even find this to be the reason behind your strange craving for tomato juice when flying; the dry air makes it taste less salty than usual.
You could also temporarily lose hearing due to the humidity and change in air pressure as you fly- a good excuse to switch off from the conversation for a few hours.
6. YOUR BODY CLOCK GETS CONFUSED
We all know about jet lag - that feeling of battling the tiredness and inconvenient four hour naps in the middle of the afternoon. Flying west to east, crossing two or more time zones, throws the body clock off even more due to the increase in daylight hours. The brain likes to actually work on a 25-hour clock rather than the expected 24-hours, making it harder to get over jet lag when you are travelling to places like Australia and New Zealand. Getting yourself well prepared before you fly would be helpful; try to take afternoon naps and sleep a little later than usual.
7. YOU'RE EXPOSED TO COSMIC RADIATION
During a seven-hour flight, for example London to New York, you are exposed to the same radiation dose as an X-ray- so imagine the exposure travelling to somewhere like Australia. As altitude increases, the cosmic radiation exposure also increases as the Earth's atmosphere provides less protection.
But, don't panic. The public dose limit is 1 mSv per year (applying to the unborn child too). To put this into perspective, this dose is equivalent to flying from London to Singapore to Melbourne 23 times. Aircrew who regularly fly 10-20 hours per week can exceed this dose quite easily. But if you're the average traveller for business or pleasure, you shouldn't let this be a reason to stop you boarding a plane.