You're Only About 43% Human
For decades, the "fun fact" circulated that bacteria outnumber human cells 10-to-1 in our bodies. In 2016, researchers at the Weizmann Institute finally did the math properly—and the truth is both less dramatic and somehow weirder.
The average human body contains about 30 trillion human cells and 39 trillion bacteria. That's roughly 1.3 bacteria per human cell, making you about 43% human by cell count. The numbers are so close that the researchers noted, with perfect scientific deadpan: "Each defecation event may flip the ratio to favor human cells over bacteria."
Most of those 39 trillion bacteria live in your colon. They're part of your microbiome—the community of microorganisms that helps digest food, train your immune system, and even influence your mood. You're not just you. You're a walking ecosystem.
For decades, the "fun fact" circulated that bacteria outnumber human cells 10-to-1 in our bodies. In 2016, researchers at the Weizmann Institute finally did the math properly—and the truth is both less dramatic and somehow weirder.
The average human body contains about 30 trillion human cells and 39 trillion bacteria. That's roughly 1.3 bacteria per human cell, making you about 43% human by cell count. The numbers are so close that the researchers noted, with perfect scientific deadpan: "Each defecation event may flip the ratio to favor human cells over bacteria."
Most of those 39 trillion bacteria live in your colon. They're part of your microbiome—the community of microorganisms that helps digest food, train your immune system, and even influence your mood. You're not just you. You're a walking ecosystem.
For decades, the "fun fact" circulated that bacteria outnumber human cells 10-to-1 in our bodies. In 2016, researchers at the Weizmann Institute finally did the math properly—and the truth is both less dramatic and somehow weirder.
The average human body contains about 30 trillion human cells and 39 trillion bacteria. That's roughly 1.3 bacteria per human cell, making you about 43% human by cell count. The numbers are so close that the researchers noted, with perfect scientific deadpan: "Each defecation event may flip the ratio to favor human cells over bacteria."
Most of those 39 trillion bacteria live in your colon. They're part of your microbiome—the community of microorganisms that helps digest food, train your immune system, and even influence your mood. You're not just you. You're a walking ecosystem.
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"Did you know that bananas are berries? I do now, and I can't unlearn it. Thanks a lot."
Crazy Fun Facts
1 crazy cool fun fact every morning. Always be coolest, funniest, smartest person in the room ;)
"Did you know that bananas are berries? I do now, and I can't unlearn it. Thanks a lot."
“I subscribed for the facts, but honestly I just love getting emails"
"This newsletter cured my fear of learning things"
"My dog learned to read just to enjoy these facts with me"
"I learned that octopuses have three hearts. I still only have one, but knowledge is power"
"Finally, a newsletter that respects my 47-second attention span"
"Fun fact: I now know more about mantis shrimp than my actual job"
"I brought up the immortal jellyfish at Thanksgiving. The family is concerned."
"Told my boss these facts came from Harvard research. Got a raise. Feeling dangerous."
"I forward these to my ex just so they know what they're missing (facts, not me)"
"My FBI agent definitely enjoys these too"
"Did you know that bananas are berries? I do now, and I can't unlearn it. Thanks a lot."
Crazy Fun Facts
1 crazy cool fun fact every morning. Always be coolest, funniest, smartest person in the room ;)
"Did you know that bananas are berries? I do now, and I can't unlearn it. Thanks a lot."
“I subscribed for the facts, but honestly I just love getting emails"
"This newsletter cured my fear of learning things"
"My dog learned to read just to enjoy these facts with me"
"I learned that octopuses have three hearts. I still only have one, but knowledge is power"
"Finally, a newsletter that respects my 47-second attention span"
"Fun fact: I now know more about mantis shrimp than my actual job"
"I brought up the immortal jellyfish at Thanksgiving. The family is concerned."
"Told my boss these facts came from Harvard research. Got a raise. Feeling dangerous."
"I forward these to my ex just so they know what they're missing (facts, not me)"
"My FBI agent definitely enjoys these too"
"Did you know that bananas are berries? I do now, and I can't unlearn it. Thanks a lot."
"Did you know that bananas are berries? I do now, and I can't unlearn it. Thanks a lot."
“I subscribed for the facts, but honestly I just love getting emails"
"This newsletter cured my fear of learning things"
"My dog learned to read just to enjoy these facts with me"
"I learned that octopuses have three hearts. I still only have one, but knowledge is power"
"Finally, a newsletter that respects my 47-second attention span"
"Fun fact: I now know more about mantis shrimp than my actual job"
"I brought up the immortal jellyfish at Thanksgiving. The family is concerned."
"Told my boss these facts came from Harvard research. Got a raise. Feeling dangerous."
"I forward these to my ex just so they know what they're missing (facts, not me)"
"My FBI agent definitely enjoys these too"
"Did you know that bananas are berries? I do now, and I can't unlearn it. Thanks a lot."