What are varicose veins and spider veins?

The heart pumps blood to supply oxygen and nutrients to all parts of the body. Arteries carry blood from the heart towards the body parts, while veins carry blood from the body parts back to the heart. As the blood is pumped back to the heart, veins act as one-way valves to prevent the blood from flowing backwards. If the one-way valve becomes weak, some of the blood can leak back into the vein, collect there, and then become congested or clogged. This congestion will cause the vein to abnormally enlarge. These enlarged veins can be either varicose veins or spider veins. Varicose veins are very swollen and raised above the surface of the skin. They are dark purple or blue in color, and can look like cords or very twisted and bulging. Spider veins are similar to varicose veins, but they are smaller, are often red or blue in color, and are closer to the surface of the skin than varicose veins. They can look like a tree branch or spider web with their short jagged lines. Spider veins can be found on both the legs and the face. They can cover either a very small or very large area of skin.