How Do Collagen Supplements Work? What the Science Says

Collagen is the glue that holds your entire body together. That’s not just an expression — this protein powerhouse literally forms the connective tissue for almost all of the structures in your body, from your bones to your skin.

It’s an important building block for whole-body health — which explains why people are stirring collagen supplements into their coffee to get an added protein boost. Collagen reduces wrinkles, keeps your joints strong and flexible, supports strong bones, and increases skin hydration.^[1][2][3][4]

Your body naturally produces collagen every day. But over time, that production slows down. “There is an enzyme in our skin called collagenase, which breaks down collagen,” says Debra Jaliman, MD, author of “Skin Rules: Trade Secrets from a Top New York Dermatologist.” “After the age of 25, we break down more collagen than we make, so that’s why we start to see fine lines and wrinkles.”

You can add more collagen to your diet by regularly consuming foods like bone broth and organ meats. If that doesn’t sound like your cup of tea, collagen supplements are an ultra-convenient way to reap the benefits of this powerful protein.

But do collagen supplements really work? Here’s a quick-and-dirty guide to what the research says.

Related: Supplements for Better Hair, Skin, and Nails

How do collagen supplements work?

Your body is filled with cells that have specific jobs to keep your engines running. Fibroblasts have an important job: they produce collagen. In order to make the magic happen, fibroblasts need access to amino acids — namely, glycine, proline, and hydroxyproline. Collagen supplements supply your fibroblasts with amino acids so they can continue to do what they do best.

Hydrolyzed collagen, also known as “collagen peptides,” is the most effective way to deliver these amino acids. The hydrolyzing process breaks down collagen into a smooth, light powder. The final product has a low molecular weight, so your system has an easier time digesting, absorbing, and distributing the amino acids throughout your entire body.^[5] That makes the amino acids more bioavailable — a fancy way of saying “actually able to be used by your body.”

Collagen supplements and digestion

One critique of collagen supplements is that your stomach acids break down the collagen peptides before they can start doing any good stuff. “Collagen is a large molecule, but [due to] the way modern collagen is made or how it’s hydrolyzed into collagen peptides, we are capable of digesting the compound,” says nutrition expert Kelly Schmidt, RD, LDN, and founder of the holistic practice Kelly Schmidt Wellness.

Collagen supplements are digested into amino acids and peptides in your gut. In order to be used by your body, those amino acids and peptides have to be absorbed by the small intestine and circulated into your bloodstream.

“Research has proven that after ingesting collagen in the hydrolyzed form, it increases in the blood,” Schmidt says. A 2018 study investigated the effects of ingesting hydrolyzed collagen over a four-week period.^[6] The results found changes in the levels of hydroxyproline peptides in the bloodstream. Other studies have also found levels of collagen peptides in the bloodstream after ingestion.^[7][8]

So, yes, collagen supplements provide important building blocks for your body to make more collagen — even after digestion.

Why take a collagen supplement? Unless you routinely eat buckets of bone broth and organ meats, you probably don’t have enough naturally occurring collagen in your diet — if at all. It’s easier to use a supplement that you can add to smoothies, soups, baked goods, and your favorite drinks. To get the most bang for your buck, look for a flavorless formula that blends in quickly and without clumps.

“Like any supplements, there are some brands and forms of collagen better than others. Look for labeling to indicate the collagen peptides do not have fillers and that it’s from a grass-fed product,” Schmidt says.

Shop now: Bulletproof Collagen Protein Powder

What does collagen do?

According to Anne Kelly, MD, medical director at the Holland Biomedical Clinic and Minnesota Hyperbaric Treatment Center, “I think of collagen as another ingredient in the recipe that delays aging, but it’s not just a beauty product for the skin. It is the brick-and-mortar foundation for multiple functions in the body.”

Here’s a quick look at the benefits of collagen supplements.

Skin

“Collagen is the most abundant protein in the skin. It makes up 75 to 80 percent of your skin,” Jaliman says. “The middle layer of the skin is called the dermis, and that is where we find the collagen and elastic tissue. This is the layer that gives the skin its fullness and plumpness.”

Studies have shown that regularly ingesting hydrolyzed collagen can support overall skin health and combat the effects of aging. It can reduce the appearance of wrinkles, increase skin hydration and smoothness, and support skin elasticity.^[9][10] “Collagen consumption can increase skin elasticity and can help your body’s skin repair process, thus encouraging your body to form new collagen,” Jaliman says.

Joints

In addition to supporting overall bone and joint health, collagen can decrease joint pain, improve flexibility, and help form new bones.^[11][12] This is a big deal for collagen’s anti-aging benefits, but it’s also good news for people who work out: a 2008 study of 147 athletes at Penn State University found that collagen supplements helped reduce joint pain.^[13]

Related: How to Choose the Best Protein Powder for Your Body

You deserve to feel your absolute best. Collagen supplements are effective and versatile, and they benefit your body from the inside-out. Learn more about the difference between collagen protein and gelatin.  Check out this roundup of collagen peptide recipes for delicious ways to use your collagen protein powder.