On your holiday travels, watch out for DVT

Next week, millions of Americans will be flying on airplanes to head home for Thanksgiving. And a common health concern for travelers is the risk of developing deep vein thrombosis. DVT occurs when a blood clot develops in the large veins of the leg or pelvic area. It's generally caused by sluggish blood flow through the vein, usually from sitting in cramped positions for long period of times. Some studies show the cabin pressure of an airplane also plays a role.

But just how dangerous is DVT? According to the American Heart Association, it affects up to 2 million Amerans per year. The good news is, in most cases, its not life threatening. The biggest concern is something known as pulmonary embolism, which occurs when the DVT blood clot travels from the leg to your lungs. It accounts for nearly 200,000 deaths a year.

Know if you're at risk: Most people think DVT strikes just older adults, but a large long-term study showed that women taking birth control, people over 6 feet 1 inch tall, and adults under 30 are at increased risk as well. The more frequently they traveled, the higher the risk became. Experts say most cases of DVT develops on flights over four hours in length.

Look for the red flags: If your leg, ankle or feet are swelling, warm to the touch or cramping during a flight, that may be a sign of DVT. Also, the sudden onset of shortness of breath, anxiety or chest pain may be a warning of pulmonary embolism, or a blockage in a lung artery.

You can reduce your risk of developing DVT by staying hydrated before and during flight. But avoid beer and soda. Alcohol and anything with caffeine add to dehydration and jet lag. The most important thing is to get up and walk around every 30 to 45 minutes to get the blood flowing in your legs.

Be sure to tune in to Dr. Sanjay Gupta every weekend on HOUSE CALL. You'll find the answers to your medical questions Saturday and Sunday at 8:30 a.m. ET on CNN.