They're unsightly, they tend to get worse over time, and they're very common.
Veins carry the blood from the legs back to the heart.
They work against gravity, and valves inside the veins help push the blood along, preventing backflow. In some people these valves are missing, or they don't function properly. This causes the blood to pool in the lower leg, dilating the veins and causing them to bulge. There are four main risk factors for varicose veins. To begin with, women are five times more likely to get them than men are.