Are we really outnumbered by bacteria?

Are humans really outnumbered by bacteria 10 to 1? For decades, one of the most repeated claims in microbiology has been that bacterial cells outnumber human cells by a ratio of 10:1. It is a memorable idea, and one that has shaped how many of us think about the human microbiome. But where did that number come from, and is it actually true? In this inaugural episode of Microbially Speaking, we explore the origins of the 10:1 microbiome myth, the early work of Thomas Luckey in intestinal microecology, updated estimates of human and bacterial cell numbers, and why the real ratio is likely much closer to 1:1. Along the way, we discuss what these numbers mean for our understanding of the human microbiome, infection prevention and control, antimicrobial stewardship, and the complex relationship between humans and the microbial world. If you’re interested in microbiology, infectious diseases, infection control, antimicrobial resistance, or the hidden microbial ecosystems that shape our health, subscribe for more episodes of Microbially Speaking. You can also check out this Episode on Spotify: https://open.spotify.com/episode/5FJkpFkFYurFLmQjcnX4dS?si=XxanIOD6QD2YBq2jPQI9xg References: An estimation of the number of cells in the human body https://www.tandfonline.com/doi/full/10.3109/03014460.2013.807878 Revised Estimates for the Number of Human and Bacteria Cells in the Body https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.1002533 Microbial Ecology of the Gastrointestinal Tract https://www.annualreviews.org/content/journals/10.1146/annurev.mi.31.100177.000543 Introduction to Intestinal Microecology https://pubmed.ncbi.nlm.nih.gov/4639749/ Sir Samurai T. D. Luckey, PhD https://pmc.ncbi.nlm.nih.gov/articles/PMC2477726/ #Microbiology #Microbiome #InfectionControl #InfectiousDiseases #AntimicrobialStewardship #MicrobiallySpeaking