If you’re under the impression that blood inside the body is blue, you’re not alone.
There is a longstanding myth that blood inside of our bodies is blue.
While some animals do have blue blood, human blood is red.
Elizabeth Fernandez / Getty Images
Blood both inside and outside of our bodies is red due to the presence of pigment found inhemoglobin.
This article will discuss why blood is red.
Elizabeth Fernandez / Getty Images
Why Do Some People Think Blood Is Blue?
There are a few reasons people may think blood inside the body is blue.
A longstanding misconception about blue blood stems from the way that veins look through the skin.
How veins appear is affected by how light is filtered by the skin.
The color of bruises andhematomas(collections of blood) are also dependent on light filtering through the skin.
What Color Is Blood?
Blood in humans is red.
The proteinhemoglobinmakes blood red.
This important protein is found in red blood cells and carries oxygen to tissues throughout the body.
Why Do Veins Appear Blue Through the Skin?
If you take a look at your wrist, you may be able to see some superficial veins.
They might appear blue, purple, and/or green depending on your skin tone.
Visible light is composed of a range or spectrum of wavelengths that travel through space.
People with darker-toned skin may notice cyanosis more prominently in the gums,lips, and around the eyes.
If you have cyanosis unrelated to a cold environment, seek medical attention immediately.
Summary
Despite misconception that human blood is blue, blood is, in fact, red.
Depending on the amount of oxygen present, it may be dark, deep red or bright red color.
Hemoglobin is a protein in the blood of humans that is responsible for the red color.
Certain other animals do have blue blood due to the presence of a different pigment in their blood.
Veins appear blue, green or purple because of the way that skin tissue absorbs and reflects light.
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