Washing Habits Can Change Skin Microbiome and Affect Skin Health

A recent study conducted by researchers at George Washington University suggests that maintaining cleanliness behind the ears and between the toes can contribute to healthier skin in these areas.

The study highlights the significance of the skin microbiome, the community of microorganisms residing on and within the human body, in influencing overall human health. The research conducted by the George Washington University team reveals that the skin microbiome’s composition differs in dry, moist, and oily regions of the skin.

The researchers at the GW Computational Biology Institute embarked on a comprehensive examination of the skin microbiome in individuals who are in good health. Led by Marcos Pérez-Losada, an Associate Professor specializing in biostatistics and bioinformatics at the GW Milken Institute School of Public Health, the team aimed to investigate a concept they referred to as “the Grandmother Hypothesis.”

Keith Crandall, Director of the Computational Biology Institute and Professor of biostatistics and bioinformatics at GW notes that his grandmother always instructed the kids in his family to “scrub behind the ears, between the toes and in the belly button.” Crandall suggested that these particular skin hotspots tend to be less frequently cleansed compared to areas like the arms or legs, potentially harboring distinct bacterial communities.

To explore the validity of the Grandmother Hypothesis, Pérez-Losada and Crandall developed an innovative genomics course and enlisted a team of students to undertake this investigative journey.

A total of 129 graduate and undergraduate students were instructed in data collection techniques. They swabbed specific, moist, and oily hotspots, including behind the ears, between the toes, and the navel. In addition, they gathered samples from control areas with dry skin, such as the calves and forearms.

Subsequently, the students were trained in the techniques of DNA extraction and sequencing from the skin samples, enabling them to compare the microbial communities inhabiting the hotspots with those in the control areas.

The outcomes of the study revealed that the forearms and calves, which are typically subjected to more thorough cleansing during bathing, exhibited a higher diversity of microbes. This greater diversity potentially signifies a healthier assortment of microorganisms when compared to the samples collected from the designated hotspots.

Crandall emphasizes that when certain troublesome microbes dominate the microbiome, they can disrupt the delicate balance crucial for maintaining skin health. If this microbial equilibrium tilts in favor of harmful microbes, it can lead to skin conditions such as eczema or acne.

The students' findings substantiated the Grandmother Hypothesis, indicating that one's cleaning practices can indeed influence the composition of the skin microbiome, thereby impacting the overall health of the skin, as noted by Crandall.

This research, which builds upon a previous study conducted by the same team, represents one of the initial explorations into the diversity of sites within the skin microbiome of healthy adult individuals.

It serves as a valuable reference point for forthcoming research endeavors. Crandall emphasizes that the study of how the assembly of skin microbes contributes to either health or disease is still in its nascent stages, indicating the vast potential for further investigations in this field.