The “Grandma Hypothesis” and the areas of the body that you should keep very clean

To get an integrated view of the spatial diversity of skin bacteria, the research team at the GW Institute for Computational Biology studied five skin regions for four years, from 2019 to 2023 – the navel, behind the ears, between the toes, the shin and the forearms. – With different physiological characteristics – dry, wet and oily – in 129 healthy adults.

Marcos Perez Losadaassociate professor of biostatistics and bioinformatics at the J. W. Milken Institute School of Public Health, and his team were interested in testing what they call “The grandmother hypothesis”.

Keith CrandallDirector of the Institute for Computational Biology and professor of biostatistics and bioinformatics at George W. University, his grandmother always told the children in his family to “rub behind their ears, between their toes, and in their belly buttons.” These hot spots are washed less frequently than the skin of the arms or legs, and therefore can harbor different types of bacteria, Crandall said.

But does the novelty hypothesis hold up if tested? Pérez-Losada and Crandall designed an innovative genomics course, then launched a team of students to help them figure it out.

Novelty thesis

129 graduate and undergraduate students were taught how to collect their own data, taking samples from some moist, oily spots, behind the ears, between the toes, and at the navel. They also collected samples from drought control areas such as calves and forearms.

The researchers found that forearms and legs, which are often cleaned more thoroughly at bath time, had a higher diversity and therefore a healthier set of microbes compared to samples taken from critics’ points.

Eczema or acne

When certain problematic microbes take over the microbiome, it can throw health off balance, Crandall says. If the microbiome is leaning in favor Harmful microbesThe result can be skin diseases such as: Eczema or acneThe researchers say in a statement.

The students tested the novelty hypothesis, and their results suggest that cleaning habits can change the microbes that live on your skin, and thus your health, Crandall says.