Michael: Your body has over 160,000 kilometers of blood vessels working hard to get oxygen to your cells and keep you alive. Arteries carry oxygen-loaded blood away from your heart and lungs while veins take carbon dioxide-loaded blood back for recycling. For the most part, your circulatory system runs smoothly, but because the veins below your heart, especially the ones in your legs, have to work against gravity, sometimes things can go wrong.

Changes like getting older or gaining extra weight can make blood pool up and form lumpy vericose veins. See, veins have a bunch of one-way valves to make sure blood flows towards the heart without backtracking, but there are a lot of ways these valves can stop working.

One is age. As you get older, your muscle fibers get thinner and weaker, so the vein valves can't open and shut as smoothly anymore. Malfunctioning valves can also be hereditary, so genetics might be a factor. Thirdly, obesity can make you more prone to thes e bulging blood vessels. That's because more body weight means more pressure on your legs, and higher blood pressure in your veins - called venous hypertension.

Compared to arteries, vein walls are relatively thing, so higher blood pressure can make your veins balloon out and keep the valves from closing properly. Some studies have found that vericose veins have more structural proteins, like collagen and elastin, than normal veins. As your body tries to handle the extra stress of high blood pressure, maybe your veins swell up as an intentional biological response.

And lastly, pregnancy can also cause vericose veins. Expectant mothers carry around extra blood to support a fetus and the cocktail of pregnancy hormones can relax the walls of their blood vessels so veins could bulge out more easily.

For most people, vericose veins are just a cosmetic problem, but for some, they can be painful health issues. To treat vericose veins, doctors might suggest using compression clothing to help squeeze your legs like a tube of toothpaste to help your veins pump blood to your heart more easily. If that doesn't work, some doctors might use a laser treatment or sclerotherapy where they inject a salt solution to irritate the vein so your body seals it off. Because you have lots of blood vessels, your body can handle a couple of superficial veins scarring over.

In the long run, your best bet to prevent vericose veins is to remember to move around rather than sitting or standing still for hours to help your veins do what they do best.

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