What is the 'grandmother method' of bathing
You've probably received advice from your grandmothers on the proper way to take baths. Interestingly, scientific research in microbiology has now provided a backing to these age-old practices. Scientists, in pursuit of understanding the most efficient methods of personal hygiene, discovered that many people overlook certain areas during cleansing, resulting in a less healthy microbiome. This led them to formulate the "grandmother hypothesis."
Study focussed on skin biomes
The study concentrated on the skin microbiome, which are the innumerable microscopic microorganisms/microbes that live on human skin. If given the right care, these microbes are essential to preserving our skin health. One of the ways to give proper care is by taking a bath properly. That is where the need for a proper showering technique emerged, eventually leading to the "grandmother" technique.
How the term came into being
In a statement on the findings, Keith Crandall, director of the Computational Biology Institute at George Washington University, said that his grandmother always told him to scrub in the belly button, between the toes, and behind the ears. He stated that these areas of the body where you had to be reminded to clean would harbor different kinds of germs than other body parts.
About the study
To obtain samples for their study, the researchers first collected samples from the forearms and calves of 129 students. Then they collected samples from their navel, between their toes, and behind their ears. The students were then instructed to sequence the DNA in those samples and compare the results between the often-cleaned areas and the more difficult-to-reach areas.
Conclusions of the study
As it turned out, Crandall and his grandmother were correct: regions with regular cleaning had a far more varied microbiome than neglected ones and included a potentially healthier assortment of bacteria. In comparison to sebaceous (behind ears) and moist (belly button and between toes) skin regions, dry skin regions (forearms and calves) were more even, richer, and functionally distinctive.
It's all about balance
Your skin microbiome is made up of both beneficial and harmful microbes. Eczema and acne are examples of disorders that can arise when the balance tips in favor of the harmful microbes, according to Crandall. This study provides a reference point for healthy microbiomes in adults, but further research is still needed to fully understand the relationship between human health and microbiome health.
