Having many noticeable veins in your feet may be a symptom of varicose veins. Veins enlarge due to damage to veins in the feet or increased pressure in the leg veins, but it is rarely a serious problem. Furthermore, it is often genetic.
Women are more likely to develop varicose veins than men, especially during pregnancy. However, it also occurs naturally as bodies age. More serious causes of varicose veins include damage to deep veins, perforation of veins, blood clots and, in rare case, tumors. One way to prevent varicose veins is regular exercise. Contact a doctor if you believe the problem may be serious or you are experiencing other symptoms.