In the skin of your face, a gigantic community of mites already lives. They are called follicular mites (Demodex folliculorum) and lives only in humans.
They measure two hundredths of a centimeter, so they can fit loosely into a follicle of your skin. They are provided with claws and a mouth, with which they can pass through the skin cells. But they don't just generate excrement, because they have no anus (and we don't even know what they eat).
Actually, there are two species of mites that live on your face: Demodex folliculorum Y D. brevis. They are arthropods, the group that includes animals with articulated legs, such as insects and crabs. Being mites, their closest relatives are spiders and ticks.
Under the microscope, they look as if they were swimming through oil. The two species live in slightly different places. D. folliculorum resides in the pores and hair follicles, while D. brevis prefers to settle more deeply in the sebaceous glands.
Compared to other parts of your body, your face has larger pores and more numerous sebaceous glands, which may explain why mites tend to live there. But they have also been found in other places, including the genital area and in the breasts.
In 2014, it became clear how omnipresent they are. Megan Thoemmes and his colleagues at North Carolina State University, in Raleigh, found Demodex DNA on each of the faces they analyzed.
That suggests that we all have them, and probably quite a large number. In other words, there can be about two mites per tab. Populations may vary from person to person, so some will have many more than others. You can also have more mites on one side of the face than on the other. However, it is not clear what mites get from us. To get started, we are not sure what they eat.
Some think they eat dead skin cells. Some think they are eating fat from the sebaceous gland. Thoemmes and his colleagues are currently examining the microorganisms that live in the bowels of mites. That could help determine your diet.
Nor do we know much about how they reproduce. It seems that they leave at night to mate and then return to their pores. All we know is that they lay eggs, as you can see in the following video:
Female Demodex mites lay their eggs around the edge of the pore in which they live. But probably not many. His eggs are quite large, from one third to half the size of your body, which would be very demanding at the metabolic level.
When a Demodex dies, its body dries up and all accumulated debris degrades on your face. But do not worry, it seems that these mites are not harmful. However, if we have too much, then we can suffer rosacea (a chronic inflammatory skin disease): instead of 1 or 2 per square centimeter of skin, the number increases from 10 to 20. But that does not mean that mites cause the problem: in a study published in 2012, it was concluded that the main cause was changes in people's skin.
And this is just the tip of the iceberg. Our bodies are full of microorganisms: they constitute 90% of our cells. Because, in purity, you are not you.