There Are Thousands of Microscopic Mites Living in Our Pores and on Our Faces

At this very moment, thousands of tiny mites live deep within the pores of our faces, together with all other humans. In the most literal sense, they are the closest, lifelong companions we have. We are never truly alone.

Mites are microscopic arachnids that are related to ticks and spiders. The naked eye cannot see them, nor can their movement be felt. Face mites are thought to live the majority of their existence with their heads down tucked within skin pores. Their bodies are correspondingly elongated like the pore's shape, and they are little more than living plugs that have eight wiggling legs.

Mites are found in the ear canal, eyebrows, eyelashes, the face, and almost every part of our skin minus our palms and soles. Two species of mites are known to live on our faces. They are Demodex brevis and Demodex folliculorum. D. brevis is stubbier, shorter, and is shaped like a club, and this species likes to settle deep into our sebaceous glands. D. folliculorum is skinnier and longer and can be found in the hair follicles close to the surface of the skin.

Face mites are averse to light, do not possess an anus (so that they cannot poop), and live their whole life on the skin. Nobody knows what they eat; we only assume they feast on sebum and dead skin.

North Carolina State University, Raleigh researcher Rob Dunn and his colleagues studied these mites at the Rob Dunn Lab. A specimen can be gathered from the skin by putting a drop of superglue on it and then placing a microscope glass slide on top. After the superglue dries, the glass slide is peeled off and takes with it the contents of the skin pores, including the mites. Alternately, sebum can be scraped from the skin and put on the slide.

Face mites can also be detected by testing for their DNA from samples of sebum. Researchers have found that every person over 18 years old has face mites. These mites are ubiquitous in all humans.

Interestingly, research on DNA revealed that these mites evolved very carefully alongside their hosts, with a minimum of four separate mite lineages mirroring human evolution. These mites, like us, have distinct Asian, European, African, and Latin American ancestry.

California Academy of Sciences researcher Michelle Trautwein is Dunn's colleague who studies mite diversity. She wants to sequence the genome of the face mite so that we can know how they evolved with us and let us know more about their physiology.

Scientists have since known our body to be an ecosystem, where millions of microscopic organisms live and move and have their being. We can consider ourselves to be a microcosm of the earth or the universe. Demodex mites could be beneficial to us just as good gut bacteria help in our digestion. Maybe someday we may discover that they eat harmful bacteria on our faces or secrete antimicrobial molecules that benefit our health. We may well be in a mutualistic relationship with them, with us feeding them pore waste while they help keep our skin healthy.