Several studies in the past have claimed that sitting with your legs crossed can be harmful to your health — from raising your blood pressure and causing varicose veins to disrupting blood circulation in your legs. But while there may be some truths in these claims, it’s likely that sitting with crossed legs isn’t going to kill you. Let’s examine the myths surrounding some of these claims.

Varicose Veins

Varicose veins are enlarged veins that bulge out of the skin, typically in the legs and feet. They’re usually not serious, but they can be cause for concern if they’re painful or particularly severe. Age, genetics, obesity, and pregnancy are all risk factors, but doctors aren’t entirely sure what causes the tiny valves in blood vessels to stretch and weaken, preventing blood from flowing properly. One thing many doctors can agree on, however, is that they’re not caused by crossing your legs, despite popular belief.

“Crossing your legs does not cause varicose veins,” Dr. Jon Modrall, a vascular surgeon at the University of Arkansas for Medical Sciences, says on the university's website. “They result from an intrinsic problem with the veins themselves. Standing for long periods of time is another habit that has been questioned as a cause of varicose veins. In truth, standing may exacerbate the existing problem with veins but should not cause them.”

Blood Pressure and Heart Health

One 2007 study found that crossing your legs at the knee while you were sitting led to an increase in blood pressure, but the same result didn’t occur when people crossed their legs at the ankles. Studies completed even way before that came to similar conclusions: Crossing your legs somehow led to a slight uptick in blood pressure, even though it wasn’t necessarily enough to do long-term damage. However, since then, people have associated crossing your legs with cardiovascular risk.

Even though crossing your legs may lead to a temporary increase in blood pressure — caused by the crossed legs pushing more blood up to the heart — that doesn’t always mean it will harm your heart health, or cause a particularly risky boost in blood pressure. However, if you’re at risk of blood clots, it’s best to discuss with your doctor on how posture and sitting far too often in a sedentary position may affect your health.

Decreased Circulation

There’s little evidence that crossing your legs can cause problems for your circulation long-term. As with any other position, like sitting cross-legged or on your knees, staying in one position for too long can lead to the all-too-familiar tingling and numbness in your feet. Sitting with your legs crossed can create pressure on the peroneal nerve, which is located in the back of the knee, and may lead to this sensation. Most people will change their position when they begin to feel uncomfortable. Perhaps the key here is to avoid being completely sedentary — or to focus on improving your posture, at least while you’re sitting.

Good posture — whether standing or sitting — can improve muscle function, blood flow, and perhaps most importantly, your concentration and mental health as well. Research has found that good posture leads to improved intelligence; protects from back problems and “sitting disease”; and staves off heart disease and diabetes. It will also improve your lung function, allowing you to take fuller breaths.

So, sitting with your legs crossed may not always be bad; it’s the sitting in the same position for hours on end that can be. Fight a sedentary lifestyle by getting up to take walks every half hour, stretching, and focusing on sitting up straight.