Although our body is covered with skin, it is not made up of the same microorganisms on its surface. According to a new American study, two areas of the body in particular need to be cleaned meticulously: behind the ears and between the toes.
Rub well behind the ears: this is advice that many grandmothers gave, not without reason. An American study has just proven that the skin between the toes and behind the ears are two areas of the body that should not be forgotten to clean.
Scientifically verifying grandmother’s advice
Keith Crandall, professor of biostatistics and bioinformatics at George Washington University, reports that his grandmother always asked the family’s children at bath time to “rub well behind the ears, between the toes and the navel“.
Professor Crandall therefore hypothesized that these regions of the body, washed less often than the skin of the arms or legs, could harbor different types of bacteria. To verify this hypothesis, scientists set out to observe the skin microbiome of different healthy people, in particular that of the skin between the toes and behind the ears.
A microbiome linked to our cleaning habits
To do this, they asked 129 undergraduate students to collect their own skin microbiomes. To do this, the students had to swab the skin behind their ears and between their toes to take self-samples. They also took samples from control areas like the forearms.
Then, they proceeded with sequencing the DNA collected, in order to compare the microorganisms present in the skin microbiome of each region of the body. Result: The researchers found that forearms and calves, which are often cleaned more thoroughly at bath time, had greater diversity and therefore potentially a healthier collection of microbes compared to samples taken from hot spots.
“When certain pathogenic microorganisms become the majority within the microbiome, they can unbalance the health of the skin. says Professor Crandall. “Skin conditions like eczema or acne can result. Cleansing habits can therefore change the composition of the skin microbiome and impact skin health. he concludes.
Last August, an American doctor, Dr Jen Caudle, pointed out on TikTok the 5 areas that we tend to forget to wash in the shower: the navel, behind the ears, under the nails, the legs and between the toes.