Causes of Varicose veins
In normal vein function, veins contain multiple one-way-valves which help the blood flow upwards against gravity. When these cup like valves damage and weak or rapture then they are not properly open and close and make difficult the muscles to push blood upwards.
The blood continuous to pull in veins, increase venous pressure and damage valve points in veins became enlarge, bulky and twisted. The varicose veins are mostly effects in legs.