What Is Collagen, and Why Does Skin Make Less of It Over Time?

Key Takeaways

• Collagen is the most abundant protein in the body. According to Cleveland Clinic, it makes up about 30% of the body’s total protein.

• In skin, collagen sits in the dermis, the middle layer, where it can help give skin its structure and its visible firmness.

• According to Cleveland Clinic, the body makes less collagen over time, and the collagen it already has breaks down faster.

• Sun exposure, smoking, and a diet high in sugar can all add to that change, and Cleveland Clinic’s first suggestion is to wear sunscreen every day.

What Collagen Is and Where It Sits in Skin

Your body makes collagen on its own, and it’s the most plentiful protein you have. According to Cleveland Clinic’s overview of collagen, it’s a main building block of skin, bones, tendons, ligaments, and other connective tissue, and its main job is to provide structure, strength, and support.

There isn’t just one kind. Cleveland Clinic says 28 types have been identified, and Type I makes up 90% of the body’s collagen. That densely packed type helps give structure to skin, bones, tendons, and ligaments.

In skin, collagen lives in the dermis, the thick middle layer under the outer layer you can see and touch. Cleveland Clinic’s guide to the dermis says a net-like structure of collagen and elastin fibers there supports the skin’s overall structure and lets it move and stretch.

Why Skin Makes Less Collagen Over Time

Making less collagen is a normal part of how the body changes through adult life. Cleveland Clinic says the body produces less collagen with age, the existing collagen breaks down at a faster rate, and what remains is lower in quality. It also notes a significant drop in collagen production for women after menopause.

A few outside factors can add to that change. Cleveland Clinic names these three:

• Sun exposure: Ultraviolet light can reduce collagen production and cause collagen to break down more quickly.

• Smoking: Tobacco smoke decreases collagen production.

• Sugar: Sugar “attaches to proteins to form advanced glycation end products,” which can leave collagen “weak, dry and brittle.”

What Less Collagen Can Mean for the Look of Skin

Because collagen helps give skin its framework, a gradual drop in it may show up in how skin looks. Cleveland Clinic lists skin that looks wrinkled, crepey, or sagging among the signs that collagen levels may be falling.

Cleveland Clinic’s advice for looking after the collagen in your skin is simple: Wear sunscreen every day and don’t smoke. For routines built around visible lines, our guide to softening the look of wrinkles walks through what the evidence supports. Our guides to tightening the look of neck skin and softening the look of crepey skin cover the neck and the body.

Frequently Asked Questions

Can you measure your collagen level?

Not directly. Cleveland Clinic says collagen can’t be measured with something like a blood test, though changes, such as visibly wrinkled or sagging skin, can be signs that levels are falling.

Is collagen only found in skin?

No. Cleveland Clinic says it’s also in muscles, bones, tendons, ligaments, organs, blood vessels, and the lining of the intestines.

Does everyone lose collagen at the same rate?

It can vary. Cleveland Clinic points to a gradual decline with age, a sharper drop for women after menopause, and outside factors, such as sun exposure and smoking, that can speed the change.