The Science Behind Scars
Did you know that you have a ton of skin cells?
By “a ton” I mean about 19 million!
What gets even more amazing is that these cells are constantly being replaced by new ones. In fact, your skin regenerates about once a month; the skin you have now is not the same skin (or cells) you had at the beginning of March.
The body’s ability to regenerate its cells is what makes wound (and basically any) healing possible. If the human body wasn’t capable of creating new cells FAST then something as minor as a skinned knee might cause real concern.
This ability has helped humans survive against animal attacks and major injuries for thousands of years.
This amazing feat also has a down side: scarring!
Although they are often considered a cosmetic blemish and something most people hide, a scar is actually part of the healing process.
Dr. John Newman - a cosmetic surgeon and researcher at the Laser Center of Virginia - has said that “evolution has selected [us] for scarring. Scarring is the result of a system that has learned to respond quickly to a wound.”
When you skin is cut, the body goes into emergency mode to heal the wound. It goes into this mode because the skin is the protector against foreign objects and entities. The body wants to close that area up as quickly as possible to limit the chance of infections, debris, and sickness.
In this emergency state, the body doesn’t follow the same regenerating rules as when it is usually making skin cells.
After the initial steps of stopping the bleeding and removing foreign threats like bacteria, the body begins to close the wound and lay down the foundation for new tissue.
It starts by laying down collagen. Collagen does a lot of things, but for this article all you need to know is that it is a protein that acts as a filler and strengthens new tissue that is forming.
During normal cellular regeneration, your body is stacking collagen in a tight, weaving system. When your body is repairing itself, it is stacking collagen haphazardly.
Think of it like repairing a leak in a boat that’s at sea. The main concern is making sure that the gap is closed, not that it looks pretty.
So there it is: a scar is the result of a bunch of unorganized collagen (usually located in the dermal layer) in the skin that occurs from the emergency healing mode.
But wait a minute. This whole article has been talking about how skin regenerates. The most obvious question then is: why are some scars permanent?
After all, at the beginning of this I said that you had a whole new set of skin cells than you did last month. So what’s the deal?
Skin cells regenerate through cell division from the bottom up. New skin cells are made in the lower levels and are slowly pushed to the top layer as new cells form at the bottom and old cells die at the epidermal level. This is true for both healthy and healing skin cells.
Because new cells are formed through cell division, the cells genetic material doesn’t change much and the same characteristics are passed down from one cell to the next. This is why most people with birthmarks keep their birthmarks throughout their life and the reason you don’t suddenly get one randomly.
It is also the reason that scars last for a long time. The way the collagen protein is packed in those skin cells from when you were injured is transferred to the next set and so on.
Scars that are the result from shallower, thinner cuts don’t have scar cells that are as deep in the skin layers. The cells that are being made underneath the scar are less likely to be packed with unorganized collagen strands and once you slush off your skin cells with the haphazard collagen structure, you are likely to have skin cells that are made with the normal collagen layers, which means you will have a less noticeable or no scar left.
Scars that are deeper or wider, are less likely to have as many skin cells underneath that haven’t been affected by scar tissue so will continue to regenerate cells with similar structures.
Other factors that can contribute to a permanent scar are infection during the healing process, genetics (some people naturally scar more), location of the wound, and reopening of the wound.
Most scars that last more than two years are permanent. These scars are less likely to have tissue return to its original state.
If you liked this article, please check back next Wednesday to discover 7 scar myths you probably believe!