Why Are My Veins Blue And Green?

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blue purple and green veins on legs

Ever wondered, “why are my veins blue” or “why are my veins green” when you’re certain the blood running through them is red? Or maybe you’ve noticed that veins are more visible under some people’s skin and harder to see under that of others. There are a variety of reasons why you’re veins  may be visibly blue through your skin. In some cases, it can be a sign of venous insufficiency, a condition that affects your circulation. Below we review what makes up the circulatory system, what causes veins to be blue or greenish, and whether or not you should be worried.

Veins: An Integral Part of Your Body’s Circulatory System

Your heart is the engine of your body, pumping oxygen, blood, and nutrients to all of your body’s organs and tissues. The blood vessels that are part of the circulatory system include:

  • Arteries — They carry blood that’s rich in oxygen and nutrients away from your heart to your body’s organs and tissues.
  • Veins — The veins serve the purpose of delivering the blood, now bluish in color, back to the heart. In the heart, blood gathers more oxygen in preparation to be pumped back out through arteries.
  • Capillaries — These tiny blood vessels serve as a connection between small arteries and small veins.

Your arteries are found deeper in your body while veins tend to be closer to the skin. Their visibility is dependent upon your skin color (people with fair complexions tend to have more visible veins), body composition (people with low levels of body fat also tend to have more visible veins), and the size of the veins themselves (wider veins are more visible).

Understanding Your Venous System

facts about blood flow within your veins

If Blood is Red, Then Why Are My Veins Blue?

So why do veins look blue or even green instead of red? The answer has to do with the various colors of light and how our eyes perceive them. Different colors of light have different wavelengths. Red has the longest wavelength and violet has the shortest. The rest of the colors fall somewhere in between, with blue shades having significantly shorter wavelengths than red ones. White light contains every color and all wavelengths.

When white light hits your skin, the red light’s longer wavelength means it can travel farther than blue light. It can travel under the skin, where your veins are. The red light is absorbed by hemoglobin — the protein that makes your blood red — when it reaches your veins. (Note that while all blood is red, the oxygen-depleted blood in veins is darker than the oxygen-rich blood in arteries.)

Because of blue light’s shorter wavelength, it doesn’t travel as far and is deflected more easily than red light. That means when it hits your skin, most of it is deflected back instead of penetrating the skin. Green light also has a shorter wavelength than red, which means most green light is deflected back, as well. This gives your veins the appearance of being blue or green.

(You can test this yourself by shining different colors of lights on your skin. When you shine a red light, your veins will show up as darker red. Shining a blue light on your skin will make your veins much harder to see.)

If you want to learn more about why the veins on your legs may be more visible, click the button below to check out our popular article that has gotten over 50,000 views.


Why Are My Veins So Visible?

why do veins often appear blue or green beneath the skin's surface

Why Are My Veins Blue, Should I Be Worried?

The bottom line? Whether you have blue or green veins on your legs, there’s no cause for concern. So put any “why are my veins so blue,” or “why are my veins green”
concerns to rest. Whether you can see your veins depends on how deep they are, how thick they are, the color of your skin, and how much body fat you have. Whether they look blue or green is a trick of the light, not an indication of their actual color.

However, if they have become more visible or raised, it could indicate an underlying venous condition commonly known as venous insufficiency, or vein disease. It’s important to consult a vascular specialist if you’re experiencing accompanied discomfort as well, especially after standing or walking for long periods of time.

In addition, even if your veins do not appear visible or raised, you can still have underlying venous insufficiency. Ultrasounds are the only definitive way to know if you are at risk of developing vein disease or not. A vascular specialist will utilize ultrasound technology to see if your veins have broken valves that may cause blood to pool within your legs.

Do You Have More Questions About Veins?

Do you have other questions about your veins, or are you worried about having swollen, bumpy veins in your legs? Reach out to us at USA Vein Clinics, where we specialize in treating vein problems of every kind. We will diagnose the cause of your vein problems, develop a customized treatment plan, and walk you through every stage of the treatment process.

Contact one of our clinics today by giving us a call at 888.768.3467 or clicking the button below.

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