if skin can regenerate and heal itself albeit slowly, why can’t stretch marks and scars go back to normal?



if skin can regenerate and heal itself albeit slowly, why can’t stretch marks and scars go back to normal?

In: Biology

Because as long as the skin isn’t broken and it’s ‘working’ fine, your body doesn’t care what it looks like. A cut or bruise is damage to the skin so it will heal. But technically stretch marks arnt damage, the skin did its job and allowed for rapid growth without ripping

According to my A&P professor, the cells that repair and replace skin is not that far below the surface. A cut that is not deep enough will not leave a scar. However, if you cut down into that network you’ve destroyed the regeneration center for that spot. That being said, over time stretch marks and scars often soften, or fade somewhat.

Scars are not exactly skin. After serious injury or burn, the wound is covered with blood clot, and starts to heal. Over time, wounded tissue morphs into collagen fibres – and it has different texture and density. By the way, if you heard about old wounds reopening that ships crews experienced in long voyages – this is because of scurvy. Malnutrition and lack of vitamins causes scurvy and one of the major effects of scurvy is that body can no longer produce collagen. As a result, a living body starts to disintegrate. Eat your vitamins, folks.

Skin has different sections and the top section is called the epidermis. This epidermis has about 4 different layers if cells. The bottom layer (bottom layer of the top section, so we are still in the “epidermis”) has stem cells that can divide into new skin cells as long as those stem cells at the bottom aren’t damaged. Scars happen when that stem cell layer is damaged. Think of a deep cut required for surgery vs a paper cut. Or a burn that destroys the entire epidermis. No stem cells + an open hole on your skin is going to leave you with a scar cos the body has to fill it with something so it ends up filling it with fiber (ie a scar) instead of normal skin

Stretch marks are different. The reason people get stretch marks is not really understood. Some theories have been proposed but it isn’t as cut and dry as a scar. Every human scars but not every human gets stretch marks.

But they can. It may take a long time and depends on severity, but scars and stretch marks can both heal

When your skin regenerates over time it’s replacing cells with other cells in a working network.

When there is a cut or tear in the skin, it goes into “PATCH THE HOLE MODE” and stuffs the opening with a diffrent type of cell to close it ASAP. Because lots of nasty stuff can get in via an opening. That stuff it uses to plug the hole is diffrent from normal skin, it doesn’t sweat or grow hair either for the same reason.

I’ve had gnarly scars disappear over the years..and I mean gnarly burns, knife cuts, stab wounds, motorcycle/car/industrial accidents..and a couple surgeries..

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