Why Are My Veins Blue and Green?
What color are veins? We see blue and green veins under our skin, though they are filled with red blood. But neither blue nor green is the true color of our veins. The appearance of blue is an optical effect due to the wavelengths of the different colors. Our skin reflects more red light than blue and green. This reflection is stronger around the veins, making them appear in a darker hue that our eyes interpret as blue and green veins.
Our veins are deep red when blood is pumping through them. Minus the blood, they are closer to white. Think of the small veins on a beef filet. Some people’s veins are more visible beneath their skin. This happens because skin varies in complexion and depth. The thinner and paler the skin, the more visible the veins.
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