Fodor's Travel Talk Forums - How to avoid getting swollen feet when flying?

Your podiatrist gave you good advice. It sounds counterintuitive, but you retain fluids when you're dehydrated. As my doctor explained it to me, if your body thinks it's not getting enough fluids, it starts retaining the fluids it already has. It's as if your body becomes afraid to let go of fluids because it's worried it might not get more and it needs to conserve what it has. This contributes to edema (swelling).

(Similarly counterintuitive, people whose caloric intake is extremely limited often experience a decrease in their metabolism. The reason is because if the body "thinks" it's starving, it will burn the sustenance it gets more slowly to "save" it for when it may be needed later.)

Plane travel is extremely dehydrating and diuretics will only dehydrate you further, so I would avoid those personally. Caffeine and alcohol are also dehydrating. The best thing is just to drink lots of water -- if you are well hydrated you will retain less water.

To be sure you get travel hose/stockings that fit you properly, it is best to get a prescription from your doctor and go to a place that will measure you. They are extremely expensive, but in addition to preventing edema they can also help prevent blood clots. I have two pairs. I hate wearing them, but they beat the alternative.

And try to get up every hour and walk around the plane. If you can elevate your feet, do (difficult if not impossible in coach).