Thx. Very much appreciated!
Diet and exercise are the basics of losing/maintaining weight. The idea is to take in less calories than you use on a daily basis. Eating airplane food doesn't make that easy, since most of it is full of carbs and contains way too much sodium, which can cause fluid retention. That means you'll need to try to get more exercise when you aren't flying.
Most hotels have a fitness room or swimming pool you can use for exercise. If there is no exercise room available, a brisk walk, for at least 20-30 minutes is recommended.
There are also exercises you can do just using your body, such as lunges, squats, etc that will help build muscles and help burn fat. I lost weight doing yoga, so that's another suggestion. Many hotels have dvd players in the rooms and it's easy to carry a dvd with you of your favorite exercises, whether they be yoga or some other type of exercise.
You should also have some simple blood tests done to make sure your thyroid is functioning properly, as well as making sure you don't have any issues with blood sugar levels going to high/low (diabetes)...