It is interesting to note that our the total number of cells associated with our bodies outnumbers the total number of cells comprising our bodies by a ratio of 10 to 1. It’s estimated 500 to 1,000 species of bacteria live in our guts alone. Your personal mass of microbes works out to roughly 1 to 3 percent of your total mass. If you could effectively rid yourself of them, you could immediately drop a few pounds, though you’d also likely kill yourself since many of these microbes calling you home perform vital life-preserving functions, like aiding digestion.
In recent years, researchers participating in the Human Microbiome Project, have assiduously worked to produce the first full census of our little cootie cousins. Most of the work thus far has focused upon bacteria and, to a lesser degree, viruses. Not so much for the fungus among us.
That has changed with a new study out of the National Human Genome Research Institute (NHGRI), which looked specifically at the fungal species that inhabit different parts of our bodies, inside and out. The work is published in the journal Nature.
“We did an exploration where we looked at all the different little crevices of your body,” Julie Segre, a senior investigator with the NHGRI, told NPR.
Not surprisingly, Segre and colleagues discovered scores of fungi types, more than suspected in more places than previously suspected. Most of the fungi belonged to the genus Mallassezia. The place with the most fungi were – again, no surprise – the feet, where researchers found at least 80 varieties on the heel, 60 or so between the toes and more than 40 on toenails.
No one’s sure why our feet provide such a, uh, great foothold for fungi. One suggestion is the wide variety of temperatures found there, which offer a greater choice of housing options. Segre proffered a simpler explanation to NPR: “Even those of us who wear shoes a lot still walk around barefoot, either in our homes or in locker rooms. And there’s just great exposure to fungi.”
Aside from the yuck factor, some free-booting fungi pose health hazards, minor to deadly serious. The fungal family of Trichphyton causes skin to scale, crack and itch – otherwise known as athlete’s foot. The condition is typically treated with topical ointments, but severe cases can require oral antibiotics.
- Foot fungi a thriving, diverse community (sciencenews.org)