As the exact causes of thread veins are unknown, it is difficult to establish whether they can indeed be prevented. One way to reduce the likelihood of thread veins is to modify certain behaviours that can act as a trigger: reduce alcohol consumption, avoid prolonged periods of sitting down or standing, do not use saunas or take frequent hot baths or showers.
Sunlight is another trigger that can be controlled, thus reducing your chances of thread veins making an appearance. Keep your skin covered up, or get into the habit of using a sun block to protect your skin from sunburn or damage.
Some think that diet can have an effect on the condition: a balanced and healthy diet that provides your body with the necessary nutrients will be more resistant to damage. Antioxidants, along with certain vitamins (C, E and K), are thought to be helpful at preventing thread veins.
For those people who are obliged to spend long periods sitting or standing, it could be helpful to introduce certain exercises or to ensure that regular movement helps the blood circulate back from the legs to the heart. Support stockings could also prove to be helpful as they compress the legs and encourage blood flow.