Pioneering research, significantly updated by a 2016 study published in Cell by Ron Sender, Shai Fuchs, and Ron Milo of the Weizmann Institute of Science, revealed that the ratio of bacterial cells to human cells in the average adult body is much closer to 1:1, rather than the previously cited 10:1. While earlier estimates suggested 10 times more bacterial cells, the revised calculation puts the number at approximately 3.8 x 10^13 bacterial cells compared to 3.0 x 10^13 human cells, making us an almost equal partnership. Researchers meticulously re-evaluated previous estimations, considering cell sizes, densities, and total volumes across various body tissues, particularly focusing on the colon, which hosts the vast majority of microbes. This finding fundamentally redefines our understanding of human identity, positioning us not as singular entities but as complex ecosystems where human and microbial life are intricately intertwined and codependent.
Editorial check
How this page is checked
Source trail
science.org
External links are separated from Surfaced commentary.
Reader safety
Context before clicks
Product links and external services are not presented as guarantees.
Monetization
No affiliate flag
Ads and commerce links are kept distinct from editorial text.
Surfaced take
Why It’s Fascinating
Experts were surprised not just by the revised ratio, but by the rigorous re-evaluation that corrected a long-standing 'fact' in biology, revealing how deeply ingrained some scientific myths can become. It overturns the simplistic view of the human body as a purely human-driven machine, replacing it with the understanding that we are 'superorganisms,' profoundly influenced by our microbial co-inhabitants. In 5-10 years, this refined understanding will drive more targeted microbiome therapies, such as personalized probiotics or fecal microbiota transplants, to treat conditions ranging from inflammatory bowel disease to depression. Think of your body as a bustling city, and while you are the mayor and main architect (human cells), there's an equally large and essential population of diverse citizens (bacterial cells) who keep the city running, performing vital services you can't live without. Patients suffering from chronic diseases linked to gut dysbiosis, as well as anyone interested in optimizing their health through diet and lifestyle, will benefit most from this deepened understanding. If our microbial partners are so essential to our health and even behavior, how much of 'us' is truly human, and how much is a product of this intricate symbiotic relationship?
Related
Foodvisor
Foodvisor, developed by a French startup leveraging advanced computer vision and AI, is a nutrition tracking app that uses artificial intelligence to identify…
TypingMind
TypingMind is a sophisticated web-based user interface for large language models (LLMs), created by the independent developer, Louis Pereira. Its core feature…
Enjoyed this? Get five picks like this every morning.
Free daily newsletter — zero spam, unsubscribe anytime.