Varicose veins are veins that have become engorged and swollen. They are one of the most common health problems, especially for women and for people over fifty years old. To understand exactly what a varicose vein is, it is necessary to have a basic understanding of how the circulatory system functions. In the most simple terms, arteries carry oxygen-rich blood from the heart to the organs of the body. Veins are responsible for transporting the de-oxygenated blood back to the heart. The process of returning the blood to the heart requires the veins to work against gravity, especially when traveling up and out of the lower legs. To aid this process the veins contain internal one-way valves which prevent the blood from flowing back into veins.
Varicose veins form when one-way valves inside veins fail to function properly. This means that blood is able to flow backwards and pool inside the vein, a condition known as venous reflux. Swelling takes places as the vein becomes engorged with excess blood. The swelling creates pressure on the skin and the veins bulge out from the the body. The veins often look like puffy, twisted cords and can be felt from outside the body. The pooled blood is responsible for giving varicose veins their purple or bluish appearance.
Due to gravity and the pressure from walking, sitting, and standing, varicose veins form most frequently in the lower legs. They can form anywhere in the body, however. Hemorrhoids are a form of varicose veins, as are spider veins. Although heredity is the main cause there are certain risk factors that increase the chances of developing varicose veins.
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