WEDNESDAY, May 14, 2014 (HealthDay News) — Microbe populations on people’s hands are more diverse than believed and vary depending on where people live and their lifestyle, a new study shows.

The findings suggest that studies of microbes that live on people’s skin should include participants from a wider number of regions, the researchers added.

They analyzed microbes on the hands of 15 adult women in the United States and 29 adult women in the African nation of Tanzania. All of the American women were graduate students (13 white and two Chinese-American), while all the Tanzanian women had children younger than 5, were poor and lived in cities.

The most common types of microbes on the hands of the American women were those that have been identified in previous studies, while the most common microbes found on the Tanzanian women were associated with their environment, particularly the soil.

Notably, no one in the U.S. group was a caregiver for young children and they spent the majority of their time indoors. On the other hand, the Tanzanian women lived in open-air dwellings in the city of Dar es Salaam, and spent large amounts of time outdoors.

The findings were published May 11 in the journal Microbiology.

“If we ever hope to understand how the microbiome [community of microbes] affects health and how environmental interactions alter it, we have to expand research to cover different populations,” study author Jordan Peccia, associate professor of environmental engineering at Yale University, said in a journal news release.

“The microbial population on the graduate students’ hands looks like what we think the hand microbiome ‘should look like,’ but we can’t assume that the human microbiome is a standard thing. Our research has shown that the microbial population on the things people use to interact with the environment the most — their hands — is dramatically different between groups,” Peccia explained.

More information

The U.S. National Institutes of Health has more about you and your microbes.