Scientists Reveal What Bacteria Is Actually Living In Your Belly Button

Hidden inside your belly button lies an ecosystem of bacteria. Tucked out of the way of air, light, and all too often the scrub of a wet washcloth, the navel has all the makings of a microbial hideaway. While researchers have been studying the bacteria that live on human skin, scientists have only recently taken a closer look at the belly button.

A study from 2012 analyzed bacterial communities from the belly buttons of thousands of volunteers and found that each belly button contained an average of 67 types of bacteria. The researchers found six types of bacteria in more than 80% of the navels they studied, while more than 2,000 bacteria types showed up in fewer than 10% of the subjects. However, while human belly buttons are a safe harbor for thousands of types of bacteria, most of these microbes are either beneficial or at least not harmful. This is similar to communities of microbes found all over the skin.

The study that uncovered the biodiversity of belly button microbes was part of a citizen science project run by Public Science Lab at North Carolina State University and the Nature Research Center at the North Carolina Museum of Natural Sciences known as the Belly Button Biodiversity Project. This project relied on just over 60 volunteers from across the state. Researchers swabbed volunteers' belly buttons and analyzed the bacteria they gathered from those swabs.

The Belly Button Biodiversity Project is one of the Public Science Lab's many projects. In addition to studying belly button microbes, there are projects examining microscopic mites that live on human skin, the types of bacteria living in our armpits, and the ways clothing influences microbes living on our bodies.

There are trillions of different microbes that live on your skin, your body's largest organ. These microorganisms, known as the skin microbiome, play a vital role in our health. For example, some of the bacteria in the skin microbiome keep skin slightly acidic, which helps keep harmful germs away. Other microbes can detect harmful bacteria and viruses and signal your immune system.

While the microbial community living in your belly button is a normal and healthy thing, things can sometimes go awry. The belly button can collect sweat, fibers from clothing, and oil and dead skin cells. If not cleaned regularly, this can lead to an unpleasant smell. However, if you have pain or itching in your belly button, of if it appears to start leaking a pus-like substance, there could be an infection. Infections in the belly button are more likely among diabetics with poorly controlled blood sugar and people who have had a piercing.

Keeping your belly button, and the rest of your skin microbiome, healthy is fairly simple. Regularly washing your belly button with soap and water and drying it completely afterward is key. However, aggressive scrubbing and harsh cleaners could damage the skin and harm the natural microbial communities that normally keep things balanced. Research is also finding that eating a balanced diet can help your skin microbiome.

Research is finding that the trillions of microbes on our skin play a vital role in keeping us healthy. Thanks to citizen science volunteers, we now know more about the microbial ecosystem living in our belly buttons.