The skin sheds about a million cells a day. If that is true, how come a tattoo on the same skin manages to stay there permanently? Why do they not shed off together? The answer to this big question is because the process of getting a tattoo involves getting the pigment much deeper in the skin, far beyond the outermost layer that shed daily.
Tattoo machines are modeled on craving machines, but today with the high technology, they are much more advanced. The tattooing machines have inserting needles filled with dye and enters the body at a frequency of fifty to three thousand times in a minute.
These needles go through the outer skin layer called the epidermis. This allows the ink to sink into the inner skin layer called the dermis, which is made of nerves, blood vessels, fibers, glands and more. As the needle penetrates the body, a wound is formed hence the inflammatory system of the body starts its process of calling immune cells to begin repairing the wounded site. They try to absorb the new particles in the body and disposing them in the blood stream.
Specialized cells known as macrophages eat the attacking material to clean the inflammatory mess. The pigment cells are too big or huge to be eaten by the macrophages cells hence they manage to stay in the dermis cells.
As the cells move through the lymphatic system, some move back to the lymph nodes full of dye while others stay on the dermis.
The body has no way of disposing the ink pigment. As a result, the dye inside them becomes visible through the skin of the person taking the tattoo.
Some particles of ink are suspended in a gel-like matrix of the dermis while others are engulfed by cells in the dermis called the fibroblasts.
Remember before the dye gets into the dermis it passed through the epidermis. As the skin heals from the wounds gained, the ink in the outer layer is shed off. It is replaced by new cells free from the dye. The top layer peels off just the same way sunburns do.
For the tattoo wound to completely heal, it can take about two to four weeks.
Cells in the inner skin layer the dermis stay there until they die, at the time of death together with the ink, they are swallowed by new cells hence the ink stays there permanently. And that is how tattoos manage to stay permanently in our skin despite the skin shedding its cells day in day out.
With these permanent tattoos, we are aware that they can still be erased from our body. How does that happen? The laser again penetrates through the epidermis to the dermis and blasts or tears apart the gained colors. Black color is the easiest target. The ink particles are blasted apart by the laser that are later cleared by the macrophages cells we saw earlier.