In varicose veins, the valves do not work properly allowing blood to pool in the vein and making it difficult for the muscles to push the blood "uphill." Instead of flowing from one valve to the next, the blood continues to pool in the vein, increasing venous pressure and the likelihood of congestion while causing the vein to bulge and twist. Because superficial veins have less muscle support than deep veins, they are more likely to become varicose.
Any condition that puts excessive pressure on the legs can lead to varicose veins.
The likelihood of varicosity also increases as veins weaken with age. A previous leg injury may damage the valves in a vein which can result in a varicosity. Genetics also plays a role, so if other family members have varicose veins there is a greater chance you will, too.
You can try to prevent varicose and spider veins by taking the following steps:
Exercise regularly to improve your leg strength, circulation, and vein strength.
Control your weight to avoid placing too much pressure on your legs.
Do not cross your legs when sitting and try to elevate your legs when resting.
Get regular physical activity.
Lose weight, if you have overweight or obesity.
Do not sit or stand for a long period of time.
Wear the right compression stockings.
Put your feet up.