A fascinating new study has delved into the intriguing concept known as “The Grandmother Hypothesis” when it comes to taking care of your skin. The findings reveal that many people unknowingly neglect certain key areas, resulting in an unhealthy imbalance in their skin’s microbiome.
The researchers from the George Washington University Computational Biology Institute embarked on a mission to explore the skin microbiome of healthy individuals. They were particularly interested in understanding the variations across different skin areas, such as the arms versus the often overlooked regions like the navel and behind the ears.
Keith Crandall, the Director of the Computational Biology Institute and a professor at George Washington University, shared a personal anecdote in a statement. He recalled his grandmother’s advice to “scrub behind the ears, between the toes, and in the belly button.” Crandall speculated that these neglected areas might harbor distinct types of bacteria compared to the rest of the body due to inadequate washing.
In this study, 129 graduate and undergraduate students took samples from their calves and forearms, as well as from behind their ears, between their toes, and in their navels. These students were then taught to sequence the DNA in these skin samples, comparing the neglected, oily areas to the cleaner, dry areas.
As it turns out, Crandall’s grandmother and Crandall himself were onto something. The areas that received regular cleaning exhibited a much more diverse microbiome, potentially containing a healthier collection of microbes compared to the neglected areas.
“Dry skin regions (forearms and calves) were more even, richer, and functionally distinct than sebaceous (behind ears) and moist (belly button and between toes) regions,” the team explained in their study. They also noted that there were no significant differences found across genders, ages, and ethnicities. “Within skin regions, bacterial alpha- and beta-diversity also varied significantly for some of the years compared, suggesting that skin bacterial stability may be region and subject dependent.”
Your skin microbiome consists of both helpful and harmful microbes. When the balance tilts towards harmful microbes, it can lead to conditions like eczema or acne, according to Crandall. However, the connection between microbiome health and overall human health still requires further investigation. This study serves as a valuable reference point for understanding healthy microbiomes in adults.
The study has been published in the esteemed journal Frontiers in Microbiology.
