Think of it like this: moisture acts like a magnet, attracting other moisture wherever it can. “Because the air is so dry on an airplane, moisture is not present,” she notes. “So misting your skin will make the moisture within your skin evaporate out, leaving it tight, dry and dehydrated.” Shudder to think of all that prized Tatcha Dewy Skin Mist we’ve wasted mid-flight!So how the heck are we supposed to keep our skin from shriveling up and dying when up in the air? “I would recommend not using a spray but instead apply a few drops of a well-formulated skin oil to the face every hour of a flight," Rouleau says. "This will help keep moisture in the skin where it belongs.” She recommends her own Renée Rouleau Pro Remedy Oil or try one from this slideshow of editor-approved picks