Mondo Knows Facts
Billions of body cells die and are replaced every day
Programmed cell death and division maintain healthy organ function
To keep tissues healthy and remove damaged structures, the adult body replaces roughly 300 billion cells every single day. Epithelial cells lining the gut and circulating blood cells experience the highest replacement rates, while cardiac and brain cells turn over far slower.
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Tags: cells, turnover, biology
Billions of body cells die and are replaced every day: the short answers
- Where does this come from, and can I check it?
- Programmed cell death and division maintain healthy organ function. The figure is taken from NIH, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
- Is this really a human body fact?
- Yes. It sits on the Human Body shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
- What else can I read about it?
- The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.