Outdated Medical Advice Medicine

Blood is blue inside your body and red when exposed to air

Blood is always red; oxygen changes shade but not base colour

Blood appears blue when inside your body and only turns red when exposed to oxygen.

Blood is red whether oxygenated or not. Oxygenated hemoglobin is bright red; deoxygenated is dark red. Veins appear blue due to skin filtering light wavelengths, not the blood colour. Blood is never actually blue.

Believed 1900–2010
Year Revised 2005
Why Changed Never True
Confidence Fully Debunked
Region Worldwide

Reception

8/10
7/10

Sources

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