We hear these two words all the time when we’re talking about skin care: collagen and elastin. We know they have something to do with how our skin appears. But what are these two things, and what’s the difference between them?
Collagen and elastin work together to create skin strength, firmness, and shape. Over time, aging can deplete the skin of these two key proteins.
What is Collagen?
Collagen is actually a group of proteins found naturally in the body, mostly in our connective or “fibrous” tissues. In fact, it’s the most abundant protein we have, accounting for about 30 percent of the protein content of the human body.
What are connective tissues?
They support or connect other types of tissues or organs in the body. They’re called “cellular glue” as they help give tissues their shape and keep them strong. Cartilage, fat and tendons are examples of connective tissues.
Collagen is also found in ligaments, blood vessels, bone, the cornea of the eye, and of course, in skin.
What is Elastin?
Elastin is also a protein found in connective tissues—but a different type of protein than collagen. It has the actual property of being elastic. It’s responsible for allowing tissues in the body to “snap back” to their original shape after being stretched or contracted. For this reason, it’s often compared to a rubber band.
Elastin is found in artery walls, in the lungs, in the intestines, and of course, in the skin. Imagine how blood vessels expand, for instance, when the blood pumps through, but then contract again as they empty.
Or how you can pull your skin back, but when you let go, it returns to its normal shape. Elastin is responsible for these actions.
Why Are These Two Proteins Always Referred To Together?
We often hear about these two proteins in skin care because they work together to give skin its shape and firmness. Collagen provides rigidity, while elastin allows skin to stretch—such as when we make an expression—and then return to the original shape.
You can think of collagen as the framework, giving skin its strength and foundation, while elastin allows skin to return to the shape collagen gives it after stretching or changing because of expressions.
What is the Difference Between Them?
Collagen’s main benefit is strength. It’s comprised of very strong fibers that have impressive tensile strength, and is the foundation upon which the outer layer of the skin is anchored.
Elastin is not as plentiful in the skin as collagen, but is critical for skin function. It provides softness and elasticity to skin, forming a three-dimensional network between the collagen fibers.
These proteins are also found at different depths in the skin. Collagen is plentiful in the lower layers of the dermis, whereas elastin is more in the middle layer of skin.
How Do They Affect the Appearance of Skin?
These two proteins have everything to do with wrinkles and sagging—or the lack of them.
In young skin, they are plentiful and healthy, and keep skin smooth and taut. As we age, however, we produce less of these two proteins. In addition, UV damage and other factors mess up the connective fibers in skin.
how collagen changes as we age
Collagen becomes more cross-linked and rigid, like a brick wall that is gradually marked and broken. This results in a weaker framework for skin, so it caves and bends, forming wrinkles. Wounds heal more slowly and the skin thins, becoming even more vulnerable to environmental stressors.
At the same time, as these collagen-related changes are occurring, we’re also producing less elastin. The elastin we do have also starts to lose its ability to snap back.
Imagine that rubber band again—stretch it a hundred times, and it will start to lose its ability to go back to its original shape, becoming more permanently stretched. The same thing happens as we age.
Elastin fibers lose their resilience, and the skin doesn’t snap back as well, resulting in the sagging we see around the eyes, jaw line, and neck.