Why Does Skin Age? A Look at the Dermis and Collagen

Aging is not one thing

We often see people of the same age whose skin is in different condition. Comparing the inner arm with the face makes it clearer still. Even on the same person, the inner surface that gets less sunlight is noticeably smoother.

This is why skin aging is viewed along two paths. One is intrinsic aging, which progresses naturally over time, and the other is photoaging caused by ultraviolet light. The two differ in cause and in how they show on the surface.

The change happens in the dermis

Skin consists of the epidermis, the dermis and the subcutaneous fat layer. Of these, the place that creates thickness and firmness is the dermis.

In the dermis there is a mesh structure called the extracellular matrix (ECM). Collagen builds the framework, elastin handles the force that stretches and returns, and hyaluronic acid holds water to maintain volume.

What creates and maintains this structure are the fibroblasts. When fibroblasts are active, new collagen fills in as fast as old collagen is broken down. When the balance between what is produced and what is broken down collapses, the change we call aging appears.

Intrinsic aging: thinning and diminishing

With age, the number of fibroblasts falls and their activity slows. As less new collagen is produced, the dermis gradually thins. Collagen is known to decline steadily from the twenties onward. That means it is underway long before any visible change appears.

At the same time, the subcutaneous fat layer also shrinks. When the volume that supported the skin from below is lost, the skin is left over and sags, and the cheeks and temples look hollow. This is where the change of a face looking gaunt without any weight loss comes from. The process of volume loss is covered separately.

Bone is no exception either. As the bone around the eyes and jaw diminishes slightly, the tissue covering it loses its footing. It is a process in which several layers change together, not a matter of skin alone.

What arises along this path is mainly fine, shallow lines. The skin texture itself remains relatively smooth while fine lines appear.

Photoaging: damaged and thickened

Ultraviolet light is divided by wavelength. UVB acts mainly on the epidermis, causing burns and pigmentation, while UVA has a long wavelength and reaches deep into the dermis.

UVA that reaches the dermis damages collagen fibers directly. At the same time it increases the action of the enzymes that break collagen down. Less is produced and breakdown is faster. The structure collapses at a far quicker pace than with natural aging.

The process of repairing the damaged area is not smooth either. Instead of a normal structure, abnormal elastic fiber material accumulates, thickening the skin like leather and coarsening its texture.

So the wrinkles caused by photoaging are heavy and deep. Blotchy pigmentation and pores that look stretched come with it. If intrinsic aging goes in the direction of thinning, photoaging goes in the direction of thickening and breaking down.

Comparing the inner arm with the face makes this difference visible. It is the same skin at the same age, but the amount of exposure has split the outcome.

Expression and posture leave marks too

There is one more branch to wrinkles: the wrinkles created when the same spot folds every time you make an expression. The glabella, the forehead and the eye area are typical.

When you are young, releasing the expression returns everything to normal. The dermis has enough elasticity for the fold to smooth out. But once collagen and elastin have decreased and the same movement has been repeated for decades, the line remains even after the expression relaxes. The wrinkle created by movement becomes etched into the structure.

This is why the approaches diverge. For wrinkles caused by movement, methods that act on muscle such as Botox come up, while for lines already etched in, methods that work on the skin itself are considered alongside.

Posture is involved too. Spending long periods with your head down repeatedly folds the skin of the neck and under the jaw, and the habit of sleeping pressed on one side can leave wrinkles on that side only.

It looks different at different ages

In your twenties and early thirties, changes appear mainly on the surface of the skin. Dryness, rough texture and shallow fine lines are noticed first. At this stage, basic care such as sun protection and moisturizing carries the most weight.

Moving from the late thirties into the forties, changes in volume are added. The cheeks and temples hollow and cast shadows, and the border of the nasolabial area becomes distinct. This is the stretch where working on the skin alone becomes insufficient.

From the fifties onward, sagging comes to the fore. Loose tissue descends, the facial line breaks down and the change extends to the neck. At this stage, lifting surgery is considered a realistic option rather than filling or restoring.

Of course, this division is only a rough outline. Individual differences are large depending on genetics, lifestyle and the amount of ultraviolet exposure, so we do not judge by age alone.

What can be done?

Photoaging is largely preventable. Consistent sun protection is the surest and least expensive method. It cannot undo damage already done, but it can reduce the damage that accumulates from here.

For changes already underway, the approaches divide. In the direction of working on the environment of the dermis, methods such as skin boosters and autologous ECM come up. In the direction of filling lost volume, there is fat grafting.

Where sagging has become pronounced, filling or restoring alone will not resolve it, because the amount of loose tissue is itself the problem. In such cases, lifting surgery is considered. Facelift is covered separately.

There are also parts you can manage in daily life. Smoking is known to reduce blood flow and interfere with collagen synthesis, and lack of sleep and rapid weight change also place a burden on the skin.

TheLINE does not try to reverse aging with a single procedure. That is because the stem cell and ECM approach that works on the foundation of the skin, the fat grafting that fills lost volume, and the facelift that addresses loose tissue each target a different point. In consultations, Dr. Jaeho Cho and Dr. Yoosuk Chung first distinguish whether what bothers you most right now is texture, volume or sagging, and then set the order accordingly.

It helps to set expectations

No method turns back time. Slowing the pace of progression and improving the condition are the realistic goals.

Results vary greatly from person to person. Genetic factors, cumulative ultraviolet exposure, and lifestyle habits such as smoking and sleep all play a part. That is why responses to the same procedure differ.

Every method carries the possibility of side effects and a recovery period. We recommend sorting out what bothers you most first, and then finding the method that fits in a consultation.

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