Varicose veins are twisted, enlarged veins close to the surface. They can occur almost anywhere but most
commonly occur in the esophagus and the legs.
Veins, which return blood to the heart, contain valves that keep blood from flowing backward as a result
of gravity. When these valves become weak, blood pools in the veins of the legs and causes them to bulge.
These enlarged vessels are called varicose veins. Standing and sitting for long periods of time, lack of
exercise, obesity, and
pregnancy all tend to promote the formation of varicose veins. Sometimes varicose veins are painful, but
elevating the affected leg usually brings significant relief.