Your arms, ears and toes host different bacteria

Your skin is home to a busy community of tiny living things, called the skin microbiome.

The team worked with 129 healthy students at a US university. Their average age was about 24. Each person swabbed five spots on their own skin, just once.

The spots were picked because they differ. Behind the ears is oily. The belly button and the gaps between the toes are warm and damp. The forearms and calves are dry.

The team then read the bacterial DNA in each sample to see who lived where. People joined in four different years, from 2019 to 2023.

Each area had its own crowd. The mix of bacteria was clearly different on oily, damp and dry skin. Spots of the same type, like the forearms and calves, looked the most alike.

Two groups led overall. These were common skin bacteria called Staphylococcus and Corynebacterium. Behind the ears, about 7 in 10 of the bacteria found were Staphylococcus.

Dry skin had the most variety. The forearms and calves carried the richest and most even mix. The skin between the toes had the least.

Where mattered more than who. In this group, age, gender and ethnicity made no clear difference.

The years differed, but that is hard to read. Samples from some years differed from others. But different people took part each year, so the team could not tell if skin changes over time.

This study suggests your skin is not one habitat. It is more like a map of small neighborhoods, each shaped by how oily, damp or dry it is.

So the skin on your arms and legs may have different needs from the skin behind your ears. The authors also say washing habits and skin care products may affect each area in its own way. They did not test this.

• The face was not sampled, so we cannot say how facial skin compares.
• Everyone was a healthy student, mostly young, in one US city.
• Each person gave samples only once, so the study cannot show how one person's skin changes over time.
• The DNA test used can miss some common skin bacteria.

Forearms and calves in this study carried a wider, more even spread of bacteria than the oily skin behind the ears. Below the neck, one patch of skin is not a copy of the next. The study did not test fjör, and faces were never sampled.

So we think body skin deserves care of its own, not leftovers from a face routine. Hydrolytic® Body brings our enzyme to your arms, legs and torso. On every patch of skin, the goal stays the same: support the local community that is already there.

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