Long flights can be hard on your health so it is a good idea to take into consideration the things that will protect your health when you are flying. One thing you should do is remember to get up and move around. You are only restricted to your seat when landing or departing or when the seatbelt sign is on. Moving around will help you maintain blood circulation and prevent blood clots. Turn at the waist and do some light stretching. You should also remember to drink lots of water so that you will stay hydrated. If you drink alcohol or coffee or tea, keep them to a minimum and drink water in between each serving. Use the restroom when you need to because holding it back will not be good for you. The sanitation is the big concern for most people though so carry hand sanitizer in your purse or your briefcase in case they are out in the airline washroom.