Color

Mapping Color Changes of Bruises

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Why are bruises "black and blue"? Watch what is exactly happening in your body as bruises change from blue to green to yellow to brown, and why bruises move downwards.

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Key Facts In This Video

  1. Bruises change colors because of hemoglobin, the compound in red blood cells that brings oxygen to your body. 00:19

  2. Broken capillaries under the surface of where you were injured make the outside of your skin appear bluish-black. 00:30

  3. Bilirubin is what turns bruises yellow. Bilirubin is waste we excrete, and is what gives urine its yellow color. 01:00

  4. Sometimes, bruises move downward because gravity is pulling the debris in that direction. 01:24

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