Mondo Knows Facts
Trillions of microorganisms inhabit the human body
Bacterial cells living on and inside humans match or exceed human cell counts
The human body hosts a complex ecosystem of microbes known collectively as the human microbiome. Billions of bacteria, fungi, and viruses reside in the gut, skin, and mucosal surfaces, assisting with digestion, vitamin synthesis, and immune regulation. Current estimates indicate the total count of microbial cells roughly equals the count of human body cells.
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Tags: biology, microbiome, bacteria
Trillions of microorganisms inhabit the human body: the short answers
- Where does this come from, and can I check it?
- Bacterial cells living on and inside humans match or exceed human cell counts. The figure is taken from Smithsonian, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
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