This study delves into the microbial communities residing in less-explored regions of the human skin, specifically the skin behind the ears and between the toes. While the skin’s microbial composition has been extensively studied in various body areas, these regions still need to be examined. The research aims to uncover the diversity and characteristics of microbial populations in these less visible but potentially significant skin habitats.
A new study from George Washington University suggests that Grandma was right about keeping behind the ears and between the toes clean. This study focused on the microbiome, which includes the tiny organisms living on and inside our bodies. They found that the microbes on our skin vary depending on whether it’s dry, moist, or oily.
Researchers at the GW Computational Biology Institute wanted to understand the microbiome of healthy people. They were particularly interested in something they called the “Grandmother Hypothesis.”
Keith Crandall, Director of the Computational Biology Institute and professor of biostatistics and bioinformatics at GW, says his grandmother always instructed the kids in his family to “scrub behind the ears, between the toes, and in the belly button.” Crandall posited that these hotspots are usually washed less often than the skin on the arms or legs and thus may harbor different types of bacteria.
Researchers Pérez-Losada and Crandall created a unique genomics course to test the Grandmother Hypothesis. They enlisted the help of 129 graduate and undergraduate students. These students were trained to gather data by swabbing certain moist and oily spots, like behind the ears, between the toes, and in the navel. They also collected samples from dry areas like the calves and forearms for comparison.
The students then learned how to extract and study the DNA in these skin samples. The results showed that the forearms and calves, typically cleaned more thoroughly during bathing, had a greater variety of microbes. This suggests that these areas have a healthier collection of microorganisms compared to the spots in the study.
Crandall said, “When certain trouble-making microbes take over the microbiome, they can shift the balance away from health. If the microbiome tips in favor of detrimental microbes, skin diseases like eczema or acne can be the result.”
The students confirmed the grandmother’s hypothesis, showing that cleaning habits can affect the microbes on your skin and, in turn, your skin’s health. This research, along with an earlier study by the same team, is among the first to explore the diversity of microbes on various skin sites in healthy adults. It is a starting point for future research on how these skin microbes influence health and disease.
The “Spatial Diversity of the Skin Bacteriome” new study was published in Frontiers in Microbiology on September 19.
This study underscores the microbial diversity in often-overlooked skin areas, emphasizing the importance of a holistic approach to understanding skin health. Further research in this area may lead to improved skin care practices and a better understanding of how microbial communities contribute to overall skin well-being.
Journal Reference:
- Marcos Pérez-Losada, Kelly M. Crandall et al., Testing the “Grandma Hypothesis”: Characterizing Skin Microbiome Diversity as a Project-Based Learning Approach to Genomics. Journal of Microbiology & Biology Education. DOI: 10.1128/jmbe.v21i1.2019.