What Are Collagen Peptides? And Do They Work?

Collagen peptides are everywhere right now. They’re stirred into coffee, blended into smoothies and promoted as a way to support healthier skin, joints and muscles.

But what exactly are collagen peptides? And can a scoop of that powder really transform your body, as promised?

Registered dietitian Beth Czerwony, RD, LD, explains what collagen peptides are, the potential benefits and what to know before trying them.

What are collagen peptides?

“Collagen peptides are supplements that aim to help your body replace some of its lost collagen,” Czerwony explains.

Collagen is the most abundant protein in your body. In simple terms, it helps hold your body together by providing structure and support for your:

• Skin
• Bones
• Muscles
• Tendons
• Ligaments
• Connective tissues

But as you get older, your body naturally starts producing less collagen. That decline begins as early as your 20s and continues over time.

“By age 40, you’re likely losing about 1% of your collagen each year,” Czerwony reports.

Collagen peptides — also called hydrolyzed collagen or collagen hydrolysate — are broken-down forms of collagen that are easy for your body to digest and absorb. They’re usually sold as powders or capsules and are commonly made from:

• Beef (bovine) collagen
• Pork (porcine) collagen
• Fish (marine) collagen

Potential benefits of collagen peptide supplements

Research on collagen peptides is still evolving. And the results are often conflicting.

But some studies suggest they may offer benefits for your skin, joints and bones. Czerwony explains what collagen supplements may do for your body.

Improve aging skin

As you age and your collagen levels decline, your skin naturally becomes thinner, drier and less elastic. But some studies suggest collagen peptides may help keep your skin hydrated and more flexible, which could reduce the appearance of wrinkles over time.

“The idea is that they may help firm the skin and plump it up to keep you looking a little younger,” Czerwony says.

Still, they’re not a miracle cure for aging skin — and your results may vary.

Ease joint pain

Collagen also plays an important role in keeping your joints flexible and cushioned.

As collagen decreases, your risk of joint stiffness and osteoarthritis rises. Some research shows that collagen supplements may help reduce aches and pains in people with arthritis in their knees.

“Collagen peptides may help protect your ligaments and tendons,” Czerwony says. “So, they could be worth a try if you have arthritis pain or work out a lot.”

Strengthen bones

Your bones contain large amounts of collagen. And lower collagen levels may contribute to weaker bones over time.

Studies suggest collagen peptides may help support bone strength. That means they could play a role in preventing weakening bones and osteoporosis, especially in women who’ve gone through menopause.

Support muscle mass

Collagen also makes up part of your muscle tissue. And muscle strength is important for everyone, from young athletes to aging adults.

Researchers have found that collagen supplements may help:

• Improve strength in older adults with sarcopenia (muscle loss)
• Support muscle recovery after exercising
• Improve strength and muscle mass when combined with resistance training exercise

Side effects and warnings

Studies suggest that doses of collagen peptides between 2.5 and 15 grams per day are generally considered safe.

“More research is needed on the overall benefits of collagen peptides,” Czerwony clarifies. “But it’s well documented that they won’t harm you in proper doses.”

Still, there are a few things to keep in mind:

• You may notice some GI side effects. Some people may also notice mild digestive symptoms, like bloating or fullness, when they first start taking collagen peptides.
• There are no guarantees. The research on collagen supplements isn’t clear-cut. So, whether they’ll have the effect you want is still up for debate.
• Supplements aren’t well-regulated. The U.S. Food and Drug Administration (FDA) doesn’t test or approve collagen peptides. If you choose to take them, look for ones that are NSF Certified for Sport or USP Verified.
• Ingredients matter. If you have dietary restrictions or food allergies, be sure you know what you’re getting. Marine collagen, for example, may not be appropriate if you have fish allergies.
• Even less is known about plant-based alternatives. Collagen is found naturally in the bones and skin of animals, and most research focuses on animal products. While there are some products promoted as “vegan collagen alternatives,” they haven’t been well studied.

Final thoughts: Should you try collagen peptides?

Collagen peptides probably won’t dramatically transform your appearance or erase joint pain overnight. But for many people, they may be a reasonable supplement to try.

“At worst, they may not work,” says Czerwony. “But if they do, all the better.”

Talk with a healthcare provider before starting any supplements. They can help you decide whether collagen peptides make sense for your health goals.