Many people experience foot swelling during air travel. This symptom, though usually normal and harmless, can also be a sign of a deep vein thrombosis, a dangerous condition. There are ways you can avoid foot swelling on airplanes and decrease your chances of a health problem.
It may be possible that the decreased air pressure in an airplane cabin, equivalent to the normal air pressure on a high mountain, contributes to foot swelling, but researchers have not currently confirmed this theory with data. A study conducted by the Royal Norwegian Air Force Institute of Aviation Medicine in 1988 found no difference between foot swelling or skin temperature in different pressure conditions. On the contrary, immobilization had a far greater effect on foot swelling.
Immobility constitutes the main reason why feet swell on airplanes. Sheldon G. Sheps, M.D., writing for the Mayo Clinic, outlines the problem: extended periods of sitting during flights can cause blood to gather in the feet and lower legs, making them swell.
Adding to this problem, airlines design economy class seating with limited space, so that passengers often must keep their legs in cramped positions. According to Dr. Stanley Mohler at Wright State University School of Medicine, the spacing between seat rows usually measures between 28 and 31". He recommends 40" as a minimum for health and safety.
Deep vein thrombosis, a life-threatening medical problem, can be caused by this cramped condition. For most people, foot swelling on airplanes does not have severe effects, but occasionally air travelers develop blood clots in their legs. These clots can travel in the bloodstream and eventually reach the lungs. In most cases, the clot will, even then, cause temporary symptoms such as coughing or chest pain, then pass; but occasionally it can cause death by obstructing the pulmonary artery.
Dr. Mohler refers to airplane-linked deep vein thrombosis as "economy class syndrome," and reports that many people form small blood clots without noticing or developing complications. In some cases, however, this problem can be severe or even fatal.
Avoid foot swelling and deep vein thrombosis on an airline flight by following these recommendations, based on suggestions originating from both Dr. Sheps (Mayo Clinic) and Dr. Mohler (Wright State):
Don't stay seated; walk around in the aisle at least once an hour. Perform leg motions while seated, as well: simple exercises like moving your ankles can improve circulation. Keep your legs uncrossed. Avoid wearing overly tight clothes or socks while on a flight. Since immobility makes feet swell on airplanes, anything that improves mobility helps prevent foot swelling.
Make sure to drink plenty of fluids to improve circulation: the recirculated air in an airplane cabin can cause dehydration. Finally, avoid sedating drugs and alcohol, which tend to make you sit in the same position for too long.
People taking hormonal therapy or birth control pills, or who have an increased risk of clotting for other reasons, should get medical advice before flying. Airline passengers who experience leg pain after a flight should seek medical attention.