Why Are Veins Blue?

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Veins are the literal lifeblood of your circulatory system. As we’ve discussed before, veins and vein valves work to bring the blood back up to your heart once your arteries have dispersed it throughout your body.

We all know that blood is red, so why are your veins blue?

According to LiveScience, “veins look blue because light has to penetrate the skin to illuminate them.” Red lights have longer wavelengths, and blue lights have shorter ones, thus red and blue “penetrate with different degrees of success.” The longer wavelength of red allows it to travel further under your skin to where it is absorbed by hemoglobin. The shorter wavelength of blue means that it doesn’t travel as far as red, thus it doesn’t travel as deep under your skin as the red does. In short, the shorter wavelength that “makes it back to your eye is the blue light.”

So why do only veins look blue? This is because, according to Science Blogs, “veins are the only vessels we actually observe through the skin.” Why is that the case? “Veins are larger, have thinner walls, and are more superficial than arteries.” Also, veins are located closer to the surface of the skin. This helps explain the color of your veins, and why your veins are so blue.

What about green veins versus blue veins?

If you experience green veins vs. blue veins, you don’t need to be concerned. There is no issue with your veins being green versus being blue. The color of your veins on the surface is largely due to the undertone of your skin as well as the amount of body fat you have.

What you do need to be concerned about is if it seems like your blue veins are bulging or if they become painful in any way. These are some of the signs of venous insufficiency. Venous insufficiency is something that occurs when the veins in your legs don’t allow blood to flow back up to your heart.

The major signs of venous insufficiency include dilated veins as well as swelling and a change in the color of your legs due to blood pooling in your legs. This leads to inflammation in your skin which can rear its ugly head as:

  • Itchiness
  • Open sores
  • Redness
  • Dryness
  • Oozing fluid
  • Shiny, hard areas

Ulcers are also a potential side effect of venous insufficiency, which can turn into something quite nasty if not properly treated.

See below for a list of common vein disease symptoms and the visual illustration of the impact different vein diseases have on your body, including spider veins, venous leg ulcers, hyperpigmentation, and more.

Vein Disease Chart

Find a vein clinic in your city

In order to avoid any of the above issues from causing you problems, it’s best to get your vein health checked by a vein specialist at Vein Clinics of America. This ensures that any problems are nipped in the bud at the first sign of problems. While venous insufficiency isn’t deadly, it is something that can greatly compromise your quality of life.

And luckily, it is typically something that can be treated with a minimally-invasive outpatient procedure at a vein clinic near you.

Worried about the color of your veins?

Medically Reviewed by

Dr. Satish Vayuvegula
Dr. Satish Vayuvegula is the National Medical Director at Vein Clinics of America. Certified by the American Board of Venous & Lymphatic Medicine, Dr. Satish Vayuvegula is recognized as a physician who has met rigorous standards of knowledge and extensive training in phlebology, the diagnosis and treatment of varicose vein disease and related disorders. Dr. Satish also shares his passion and expertise by serving as a board member of the American Vein and Lymphatic Society, the predominant national organization for venous and lymphatic disease.

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