So when it comes to skin survival during a long-haul flight, who better to turn to than a flight attendant? Margaret Lai has been Flight Purser (that's fancy airline speak for manager) at Cathay Pacific for seven years, and needless to say, she's got her jetset essentials down to a fine art. Here, she shares the five beauty rules to pack with you next time you fly - including why sunscreen is crucial. Who knew?

1. Don't just drink water in-flight
Everyone talks about drinking water in flight but it's important to stay hydrated pre and post flight as well. Drink a glass of water before flying and one glass of water per hour in-flight. Don't forget to keep sipping after the flight.

2. Having a glass of wine? Go one for one
A glass of wine may help you relax but it can also be dehydrating. If you do have a drink, try drinking more water to compensate. The general rule of thumb is one for one: drink one glass of water for every glass of bubbly.

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3. Pack sunscreen in your carry on to avoid UV radiation
If you love a seat with a view, great - but pull down the blinds. If you can't, make sure you bring and apply SPF. Being on a plane doesn't make you less prone to the effects of UV rays and in fact, research has shown that at 9000-metres (the level most commercial aircraft fly), the UV level is approximately twice that on the ground.

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4. Keep make-up to a minimum
This may be a contradiction considering flight attendants wear make-up in-flight but if you're a passenger, try skipping it altogether. Just like you remove make-up before bed, you should remove all make-up during a long haul flight. Doing so will also enable you to apply and re-apply moisturiser, which you'll probably need. If you aren't comfortable going bare, choose one feature to highlight and keep the rest of your make-up to a minimum.

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5. Pick silk over cotton
It may sound indulgent but the skin around your eye is a delicate area. Picking silk pillowcases and silk eye masks can help decrease the wrinkles you get from sleeping - and this goes for on the ground as well as in the air!

6. Get your beauty sleep
Skipping sleep can affect your skin's appearance and your ability to fight germs (meaning you may get sick easily - not what you want if you're heading off on holidays). Use an eye mask and earplugs even if you don't usually sleep with them - they make a big difference. You never know when someone is going to switch on their reading light, pull up a blind or if a baby is going to start crying. If sleeping in-flight is a struggle, try a soothing spray with lavender and take melatonin if necessary.

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