Your body hosts more than 80 types of fungus.

And the body part that has the most?

The heel, followed by the rest of your feet.

Researchers at the U.S. National Institutes of Health launched a study of human fungal skin diversity using DNA sequencing.

“By gaining a more complete awareness of the fungal and bacterial ecosystems, we can better address associated skin diseases, including skin conditions which can be related to cancer treatments,” said Dr. Heidi Kong, one of the authors of the study. The research was published this week in Nature.

Researchers focused on areas of the body associated with fungal infection, testing 14 sites on 10 healthy adults.

Feet, by far, host the most fungi types. Along with about 80 types found on the heel, researchers found about 60 types on toenails and 40 in toe webbing.

Arms carry between 18 and 32 types of fungi, inside the elbow, on the inner forearm and the palm.

The head and torso have the fewest types, with two to 10, depending on the site.

Though fungal infections are common, difficulties growing fungi in a lab complicated diagnosis and treatment.

Using DNA sequencing, researchers were able to identify more than 80 types of fungus. Traditional culturing methods produced just 18.

“DNA sequencing reveals the great diversity of fungi, even those that are hard to grow in culture,” said co-author Julie Segre. “The data from our study gives us a baseline about normal individuals that we never had before.”

Loading... Loading... Loading... Loading... Loading... Loading...

Researchers compared the fungi data to skin bacteria. While arms have many types of bacteria, feet have few. The study noted that while types of bacteria tend to depend on whether skin is moist, dry or oily, fungi seems to depend more on the location.

Fungi levels were similar in each person and didn’t seem to change much over time—researchers tested twice, as many as three months apart.

“The bottom line is your feet are teeming with fungal diversity,” said Segre. “So wear your flip flops in locker rooms if you don’t want to mix your foot fungi with someone else’s fungi.”