Learn what causes varicose veins, plus easy ways to mask them.

Credit: Elinor Carucci

The idea that the simple act of crossing your legs leads to trouble is far-fetched only to a degree. “Crossing your legs doesn’t cause varicose veins, but if they run in your family, it can bring them out,” says Ranella Hirsch, a dermatologist in Boston.

Why Veins Show Up

A refresher on the circulatory system: Arteries carry oxygen-rich blood to the extremities; veins bring deoxygenated blood back to the heart and lungs. “The muscles in your legs and feet power this return system,” says Robert Weiss, a dermatologist in Baltimore, and valves inside your veins keep blood moving in the correct direction. But if those valves give way (and some of us genetically have weaker ones), the blood pools, potentially causing veins to stretch, leak, and eventually protrude. The result: varicose veins, which appear as bulging lines on the legs. (Spider veins, which are like smaller versions of varicose veins, look like tiny squiggles on the skin’s surface.) Visible varicose veins are 10 to 15 percent more prevalent in women than in men, largely due to pregnancy and female hormones, both of which can weaken veins. Other contributors include standing for extended periods and being overweight, both of which can tax valves, and slacking off on exercise, since weak leg muscles can’t move blood to the heart as effectively. And if you’re genetically predisposed to visible veins, crossing your legs over the course of many years may hasten their development, as this position puts pressure on the valves.

How to Prevent Them

Start by working out. “Exercise helps control weight and keep leg muscles fit,” says Weiss. Try low-impact activities, like swimming and biking, which don’t put undue strain on the legs. Beyond exercise, opt for flats over heels, because they allow the calf muscles to contract fully. At the end of the day, sit with your legs propped higher than your heart for 10 to 15 minutes to help drain any pooled blood. And if visible veins run in your family, and especially if your legs ache, consider wearing support hose as often as possible. (Today they look more like black tights than like Grandma’s stockings.) “Support hose can help prevent blood from pooling,” says Luis Navarro, M.D., the medical director of the Vein Treatment Center, in New York City.

How to Treat Them

For small veins, the easiest and least expensive solution is a camouflaging coat of self-tanner. Water-resistant body makeup, such as Dermablend Leg and Body Cover SPF 15 ($28, macys.com), is also effective. If you want to add a golden tone to legs to camouflage small visible veins, try Clarins Delectable Self Tanning Mousse SPF 15 ($42.50, us.clarins.com). If you experience minor aches or a heavy feeling in the veins, consider taking a supplement of horse-chestnut seed extract, such as Venastat Natural Leg Vein Health ($17 for 105 capsules, drugstore.com). “While this will not erase them,” says Navarro, “it can lessen discomfort.”

For more long-lasting removal, your dermatologist can perform sclerotherapy on spider veins and smaller varicose veins. The procedure involves injecting the offending vessels with a detergent-based solution, which irritates their linings, causing the veins to close and eventually disappear. Typically, you feel pain as the needle goes in. However, a new solution, called Asclera, approved last year by the U.S. Food and Drug Administration, may take away that sting. “The substance has anesthetic properties,” says Weiss. Sclerotherapy isn’t cheap. You’ll need about two to six treatments at $250 to $500 a pop, which insurance generally doesn’t cover. To quickly cover post-sclerotherapy bruising—and even tiny veins—try Sally Hansen Airbrush Legs ($14 at drugstores).

Large varicose veins call for more aggressive treatment: endovenous laser ablation. A doctor inserts a laser fiber or radiofrequency catheter into the damaged vein to destroy it. This onetime treatment costs about $5,000, but it is often covered by insurance, since in rare cases varicose veins can cause blood clots and ulcers.

Both sclerotherapy and laser ablation may cause some bruising. To minimize this, avoid taking anything that can thin your blood, like aspirin, Motrin, or gingko, for one week before your appointment. Hirsch says that eating pineapple for a few days beforehand may also help, since “the fruit contains an enzyme called bromelain, which may help minimize swelling.”