When we think of creatures inhabiting our skin, we tend to picture bacteria or perhaps fungi. But there are also microscopic mites Demodex folliculorum that make their home in the pores of many people’s faces. These minute creatures live, feed, and even mate within the confines of our skin, often without our awareness.
How Common Are They?
It is estimated that over 90 percent of adults host these mites, which grow to about 0.3 mm in length. They are typically passed from person to person early in life—some evidence suggests transmission via close contact such as during breastfeeding. Despite their eerie reputation, these mites are nearly universal and have coexisted with humans for centuries.
What Do They Do?
At first glance, the idea of mites in your pores may sound unsettling. Yet Demodex folliculorum appear to serve useful functions. They feed on the oils—sebum—that our skin secretes, helping to clear out pores by consuming excess material. Their preferred habitats tend to be around the nose, eyelash roots, and other facial areas rich in oil production. At night, when they emerge from the follicles, they may mate and reproduce before retreating deeper into the skin by dawn.
A Genetic Decline
Recent research indicates that these mites might be in the midst of an evolutionary decline. Their genetic diversity is shrinking, and they have lost certain genes that are common in related arthropods, such as ones that protect against ultraviolet (UV) radiation. Because they dwell within skin pores and operate mostly at night, they may no longer require those genes—but the loss does make them more dependent on human hosts. Their circadian rhythm controls have also become less autonomous. Instead of internal genetic mechanisms telling them when to wake and sleep, they now often rely on cues from human biology—such as melatonin in the skin—to trigger activity.
From Parasite to Partner
Originally, the relationship between humans and these mites might have been parasitic—one party benefiting, the other possibly harmed. But over time, it appears to have evolved toward symbiosis. As the mites become more specialized and genetically reduced, their survival hinges on living in human skin. In turn, humans may gain from their presence. Far from being purely harmful, the mites help maintain skin health. By consuming excess oil and clearing debris, they may contribute to reducing pore blockage and minimizing certain skin problems.
What If They Disappear?
If these mites were to dwindle or disappear altogether, the consequences are uncertain—but potentially negative for skin health. A lack of their cleaning function might lead to clogged pores or other dermatological issues. In essence, the mites form part of a delicate ecosystem that helps keep skin balanced. Because they are so intimately linked to human skin, their loss would reflect more than an absence of creepy crawlies—it would underscore how deeply interconnected our bodies are with tiny organisms. Their disappearance might also be an indicator of broader environmental or biological shifts affecting countless species.
Can You Remove Them?
The short answer: no. These mites live deep within follicles, far beyond the reach of routine washing or skincare routines. They are largely immune to surface cleansers and typical cosmetic treatments. Fortunately, since they play beneficial roles and live in balance with us, there is no medical need to eradicate them.
Embracing the Invisible Competition
Though the idea of creatures performing nightly reproductive rituals in your pores may feel unsettling, Demodex folliculorum challenge our assumptions about “cleanliness.” Rather than pests to be eradicated, they may be silent helpers working behind the scenes. Our bodies are ecosystems unto themselves, teeming with tiny life forms—some visible, some invisible. Often, the most curious residents are the ones we never see, working quietly in the shadows of our own biology.
