Flying can be rough on your body (jet lag anyone?) and on your skin.
This might sound funny but you need to wear your sunscreen on a plane if you are flying during the day. No way around it. Why? High levels of UV rays penetrate airplane windows since the sun is more intense at higher altitudes. The thinner air simply doesn’t filter out as much harmful UV radiation. So be sure to apply sunscreen before you get on your flight.
Or better yet apply lots of moisturizer with a built-in spf. Why? Because the other issue with airline travel in the dry, low humidity airplane environment. You may find that your skin, lips, and eyes feel dry while you are flying. So before boarding slather on a rich moisturizer to combat the dry in-cabin atmosphere. Don’t forget to apply a hydrating lip balm as well. If your eye area feels dry use your moisturizer there as well.
Be sure to drink plenty of water in-flight (though this is less for your skin and more for your overall body health), and try to avoid alcohol and salty snacks (of course if the airline gives you any food these days it seems to be pretzels or peanuts. Consider buying something healthy in the airport to eat on the airplane).
You could consider bringing a facial mist or facial water with you to spray on your face during the flight. Spraying plain, regular water isn’t a good idea since once it evaporates your skin will be even drier than when it started out. Use a facial spray that has humectant ingredients in it. Ideally you should spray the facial mist or water on your skin before applying your moisturizer so that the humectant ingredients in the mist will pull water into your skin instead of from your skin. It is a risk that in low humidity environments like an airplane the humectants ingredients in your skincare products will actually pull water from your skin instead of attracting it to your skin. So the two prong approach of spraying a facial water on your face and then topping it off with a moisturizer will help avoid this problem. If you only have time to spray the mist or water in-flight (or before) that is good as well. It certainly will help to keep your skin refreshed and moisturized.
Sources and Further Reading
Simple Skin Beauty by Ellen Marmur, MD – page 51
The Skin Type Solution by Leslie Baumann, MD – page 318