The most superficial layer of our skin - Pt.1

We had already talked in previous posts about the three main layers of the skin, however, as we know that mentioning them is not enough, we are going to know each of them more in depth -literally-.

We will start with the most superficial, the one that we can see and feel, the epidermis. This layer of the skin is made up mainly of 4 types of cells.

1. Keratinocytes: Give structure to the skin and protect us from heat, toxins and external threats. They make up about 80-90% of the epidermis.
2. Melanocytes: They are in charge of producing melanin, which gives pigment to our skin and protects us from the sun by absorbing UV rays (this is why when we are exposed to the sun, our pigmentation increases).
3. Langerhans cells: They are in charge of protecting our skin from infections and function as the immune system in the body's first defense.
4. Merkel cells: They are the connection to our nervous system and are in charge of the sense of touch, sending all the nerve stimuli we receive through the skin.

All these cells live in 5 sublayers that make up the epidermis.

The process begins in the deepest layer -basal layer- which is where the cells are born, from there they begin a journey to the uppermost layer of the epidermis, called the stratum corneum, where approximately 20 layers of dead cells accumulate, of which, we shed approximately 30,000 to 40,000 each day.

The process from when the cell is born in the basal layer until it reaches the stratum corneum and desquamates, takes approximately 28 days in healthy adult skin, however, as we age the process begins to slow down, even taking longer. 60 days, and that is why as the years go by, the skin loses its luminosity and it even costs more to heal wounds and heal properly.

The stratum corneum, which is the most superficial of all and with which we have daily contact, is made up mostly of keratinocytes. These are the “bricks” of the skin that are complemented by the ceramides that are the “cement”. Ceramides are primarily a barrier of lipid esters (fat) that give our skin much of its waterproofing ability; And since water can't get through this barrier, they do double duty of keeping you hydrated on the inside and inhibiting water or harmful bacteria from getting in from the outside.

However, this sealing mechanism is not absolutely hermetic and there are mainly three ways to overcome this barrier, although we will talk about that in a future post.

See you very soon!