The Human Body

How many days does a typical red blood cell survive in the average adult's bloodstream?

Answer

120 days

After about four months of nonstop laps, worn-out red cells are dismantled in your spleen and liver, and much of their iron is recycled into new cells. Red blood cells have no nucleus — they ditch it to carry more oxygen.

Source: American Society of Hematology / Stanford Blood Center

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