I’ve often heard that you are constantly shedding old skin cells and new one are moving “up”. I’ve also heard that every seven years by the process of shedding old skin slowly, your entire body has newer skin cells. If this is true why does our skin wrinkle as we get older? I understand sagging as the underlying muscles may weaken or gravity can cause them to sag. That still does not explain small crows feet and general wrinklyness.(If that’s not a word it should be!)
For starters, regeneration is not perfect - that’s why imperfections like blemishes, scars, age spots, freckles, and so forth accumulate over time. Sometimes, you get extreme imperfections like cancer.
To some degree, skin wrinkles and thins because the underlying collagen supporting it either breaks down, atrophies, or does not regenerate itself perfectly. Sun expsoure, which damages both the skin and the repair mechanism, can hasten this. So can poor diet or illness or other hardship. That’s one reason why folks from 100 years or more back in old photographs may look older to us than their stated ages - some of those pioneers looked about 60 by our standards in their early 30’s.
Some wrinkles also arise from use - the brow wrinkles/frown lines that people use botox on are examples of that, as are “laugh lines”. The skin wrinkles because an area folds over and over and over… skin and leather are basically the same thing, you know. Just as leather over time can become worn and creased so can skin, although it happens much more slowly in skin because skin is still alive and can, in a sense, fight back. But after 40 or 50 years age takes a toll.
Aging is also in our DNA. DNA contributes to aging, the rate of cell repair and even other timer mechanisms. While the effects of aging can be minimized, until the DNA code that contributes to it can be hacked, the major battle can’t be won.