Many people suffer from swollen legs and feet while flying called gravitational edema. It is caused by accumulating fluid building in the body during a flight along with decreased mobility of the legs causing sluggish circulation. Menstruating women and obese people are at greater risks for this swelling however there are a few things you can do to help prevent this. Avoid high sodium and caffeinated foods/beverages for a few days prior to the flight, walk around as much as possible during the flight and consider compression socks/stockings.
Here are some more tips to help prevent swelling during your flight
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