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Collagen vs. Collagen Peptides: Understanding the Difference


People who are looking to improve the quality of their skin, reduce the signs of aging, relieve joint pain, and improve overall health and wellness consider taking collagen.

You may have heard of collagen and collagen peptides and are wondering how they’re different. In a nutshell, collagen is found in your body while collagen peptides are a supplement that helps replenish your body’s collagen supply.

This article shares everything you need to know about collagen and collagen peptides — their science-backed benefits, uses, bioavailability, digestibility, and some possible drawbacks of collagen supplements.

What is Collagen?

Collagen is the most abundant structural protein in your body, meaning that collagen supports major structures like your skin, hair, muscles, bones, and cartilage (*).

There are 28 known collagen types, with Type I collagen as one of the most abundant collagen molecules — it forms 90% of the organic mass of your bones and tendons, and is the major collagen found in your skin. It’s also the best-studied collagen (*).

Other types of collagen are:

  • Type II: this is found predominantly in hyaline cartilage found in your joints (*).
  • Type III: this is the major collagen found in your blood vessels, uterus, and bowel — these are tissues that stretch. It’s rich in the amino acid glycine (*).

An interesting fact about collagen — and perhaps a common cause of concern for most people — is that collagen production starts to slow down after the age of 20. This makes your skin thinner and more fragile (*).

Not just that, but the quality of collagen also decreases. Research shows that collagen bundles are well-organized in adults but they become less dense, fragmented, and disorganized with increasing age (*).

While aging affects collagen production and quality, lifestyle factors such as smoking, eating too much sugar, excessive ultraviolet light exposure (prolonged sun exposure), and too much drinking can degrade collagen and accelerate skin aging (*, *, *, *).

Supporting your body’s natural ability to produce collagen is possible by eating foods rich in vitamin C (*). Examples of vitamin C-rich foods that are also low in carbohydrates include red bell peppers, broccoli, and strawberries.

In addition, one study found that taking a glutamine supplement may stimulate collagen synthesis through proline conversion. Proline is one of the key amino acids to form collagen (*).

What are Collagen Peptides?

Collagen peptides, also popularly known as “hydrolyzed collagen” or “collagen hydrolysate” is the supplement form of collagen.

Unlike the collagen that’s already found in our bodies, collagen peptides have gone through a process called hydrolysis with the use of proteolytic enzymes like alcalase, papain, pepsin, and more (*). This results in a collagen protein supplement that’s easily mixed into cold liquids and better absorbed by your body.

The fact is that collagen peptides are not necessary to make your body produce its own collagen since it does this already from the dietary proteins you consume (which contain amino acids) — such as meat, eggs, turkey, chicken, and salmon (*).

However, many studies suggest that taking collagen hydrolysate greatly helps, especially when you’re optimizing for specific collagen benefits like improved skin health and appearance, joint and bone health, and more.

Research also reveals that collagen supplements may improve body composition, muscle recovery, and strength, especially in people who exercise (*).

Collagen peptide supplements are usually derived from bovine (cows), porcine (pork), chicken, and marine (fish) sources. They usually come in powder form but can also be sold as capsules or drinks.

Facts About Collagen and Collagen Peptides

What’s the Difference Between Collagen and Collagen Peptides?

Collagen  Collagen Peptides (Taken orally)
  • Comprises most of the structural proteins in your body
  • Forms your skin, bones, cartilage, hair, muscles, and blood vessels
  • May fight and prevent osteoarthritis
  • Increases skin elasticity, hydration, and density
  • May improve gut health by strengthening gut junctions
  • Beneficial for improving muscle mass and strength in combination with resistance training
Uses  In clinical settings:

  • Applied as a dressing to hasten wound healing in patients with burn injuries
  • May be used as injectables to instantly reduce the appearance of smile lines and wrinkles
  • Taken orally at home or anywhere for their skin, bone, body composition, and gut benefits
  • Cannot be absorbed in your digestive tract due to its length
  • Highly bioavailable since collagen has already been broken down into small peptides
  • Practically insoluble in water, just like most fibrous proteins
  • Dissolves completely in hot or cold water, so you can make collagen-boosted coffee and smoothies
  • Not digestible
  • Easy to digest
  • Collagen injections may cause skin redness, swelling, bruising, and scarring
  • Possible allergic reactions if you have fish, shellfish, and egg allergy

Collagen protein vs collagen peptides vary in their benefits (although with some similarities), applications, bioavailability, and more. We’re going to discuss each aspect below.


Full-length or unhydrolyzed collagen that’s produced by your body and collagen peptides contain 19 amino acids and they’re known for being high in the amino acids glycine, proline, and hydroxyproline. In fact, these three amino acids make up 57% of the total amino acids in collagen (*).

Moreover, hydrolyzed collagen is considered to possess antioxidant properties. Antioxidants prevent the formation of free radicals which contribute to disease and aging (* , *).

This amino acid composition makes collagen beneficial for:

  • Fighting and preventing osteoarthritis: Several works have demonstrated that taking hydrolyzed collagen, which has 33% glycine residues, may enhance cartilage regeneration by promoting collagen synthesis (*).
  • Supporting skin health and appearance: Collagen is popularly used to achieve a youthful look. One randomized, placebo-controlled, blind study investigated the effects of a hydrolyzed collagen supplement and found that skin elasticity significantly increased, including hydration, and density (*). Unlike topical products (such as creams and lotions), oral collagen supplements reach the deeper layers of the skin to restore collagen (*).
  • Repairing the gut lining: Some people consider taking collagen supplements for supporting their gut health. While it’s too early to say with certainty, collagen hydrolysate may help heal leaky gut and irritable bowel syndrome (IBS) by maintaining, repairing, and reinforcing the intestinal mucosa (*).
  • Increasing muscle mass and strength: Although whey protein is more effective for building muscle — thanks to its high branched-chain amino acid (BCAA) content — a study showed that taking 15 grams of collagen hydrolysate along with a hypertrophy resistance training program for 12 weeks resulted in an increase of skeletal muscle and muscle strength. Results were better when taking collagen than doing resistance training alone (*).


Collagen protein has many uses in medical settings, such as hospitals and cosmetic surgery clinics.

For example, in patients with burn injuries, collagen dressings may be applied to promote wound healing by depositing freshly formed fibers. A study also showed that collagen-treated wounds were considered to be more sterile than wounds that were conventionally treated (*).

During cosmetic skin procedures, collagen may be used as an injectable (commercially known as Bellafill and made from bovine collagen) to immediately reduce the appearance of wrinkles and smile lines.

In one study, 123 male and female patients received type I and type III injectable human collagen. Based on the results, 90.2% of the participants rated their results as good or excellent (*).

As for collagen peptides, which are taken by mouth, they help with your skin, bone, joints, muscles, and gut health — as mentioned in the previous section of this article.


Since collagen hydrolysate has already been broken down (from full-length collagen) into smaller peptides through hydrolysis, they’re highly bioavailable. Meaning, that the small particle sizes of collagen supplements are easily broken down and absorbed by your body.

This makes collagen peptides a great addition to your current diet — whether as a powder, pill, or beverage.


Solubility refers to the ability of a substance to dissolve in water. Between collagen peptides and collagen protein, collagen peptides are highly soluble due to their low molecular weight (3–6 KDa) (*).

That being the case, collagen powders dissolve completely in hot or cold water.

This means you can enjoy collagen peptides in various ways, such as adding a scoop to your cup of coffee (for collagen-boosted coffee) or making a delicious smoothie made of collagen peptides, unsweetened milk, and fresh strawberries.

While these options are common, you may also add collagen peptides to your soups and baked goods like muffins and energy balls.


Because collagen peptides are hydrolyzed, they’re easier to digest by your body. Upon digestion, collagen gets distributed throughout your body — wherever collagen is needed.


With all the benefits of collagen, you may be wondering if collagen protein and collagen peptides carry certain risks.

Both could cause side effects, especially if you have allergies to collagen sources like fish or shellfish and eggs. For instance, a person who’s allergic to seafood may experience itching, generalized urticaria (or hives), and difficulty breathing after taking marine-derived collagen peptides.

Another example is injecting collagen under the skin, which may cause redness, swelling, bruising, and possible scarring.

But, for the most part, collagen supplements are well-tolerated.

Whether you’re taking collagen peptides, applying collagen sheets, or receiving a collagen injection — be sure to note any allergies and work with a qualified health professional for collagen treatments.

Frequently Asked Question

Here are answers to common questions on collagen peptides vs collagen:

Which form of collagen is most effective?

The best form of collagen to take is hydrolyzed collagen or collagen peptides. Because it has undergone hydrolysis (meaning, it has been broken down), it’s highly soluble and easily absorbed into your digestive system.

What is hydrolyzed collagen?

Hydrolyzed collagen, also called collagen hydrolysate or collagen peptides, is a type of collagen that has been broken down into smaller particles through a process called hydrolysis. Hydrolyzed collagen is usually available as a powder supplement.

What is gelatin?

Gelatin has the same nutritional composition as collagen, but gelatin is partially hydrolyzed. Because of that, gelatin forms a solid gel and is often used as an ingredient in gummy candies, sauces, marshmallows, and other ready-to-eat products.

Does collagen make you gain weight?

The answer is no. There’s nothing in collagen that will cause weight gain (or kick you out of ketosis, if you’re on a very low-carb diet) unless your collagen peptides supplement contains a lot of carbs and added sugars.

Bottom Line

Full-length or unhydrolyzed collagen and collagen peptides have the same amino acids, and both are beneficial for providing structure to your body. Specific uses include reducing the signs of aging, improving bone and joint health, and supporting the gut.

One major difference is that unhydrolyzed collagen is insoluble and indigestible, while collagen peptides are the complete opposite — which is why they’re great as dietary supplements.

The average individual, a fitness enthusiast, or someone with specific needs can take a quality collagen peptides powder to boost their overall appearance and performance or receive collagen-based materials like dressings and injectables for medical purposes (such as speeding up wound healing or instantly looking younger).

Also, keep in mind that collagen levels in our bodies decrease naturally as we age; however, we can support them by living a healthy lifestyle — avoiding sugar, too much sun exposure, smoking, and drinking — and eating foods rich in amino acids (such as meat) and vitamin C.

26 References

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Henriksen K et al. Type I Collagen. 2016

Andrade F et al. Autoantibodies in Rheumatoid Arthritis. 2013

Kuivaniemi H et al. Type III collagen (COL3A1): Gene and protein structure, tissue distribution, and associated diseases. 2019 May 7

Obagi S. Why does skin wrinkle with age? What is the best way to slow or prevent this process?. 2005 September 26

Prockop D.J. Collagens. 2013

Rittié L et al. Natural and Sun-Induced Aging of Human Skin. 2015 January

Knuutinen A et al. Smoking affects collagen synthesis and extracellular matrix turnover in human skin. 2002 April

Danby F. Nutrition and aging skin: sugar and glycation. 2010 July to August

Goodman G et al. Impact of Smoking and Alcohol Use on Facial Aging in Women: Results of a Large Multinational, Multiracial, Cross-sectional Survey. 2019 August 1

Pullar J et al. The Roles of Vitamin C in Skin Health. 2017 August 12

Murakami H et al. Combination of BCAAs and glutamine enhances dermal collagen protein synthesis in protein-malnourished rats. 2012 November 8

Lopez A et al. Hydrolyzed Collagen—Sources and Applications. 2019 November 7

Lopez A et al. Hydrolyzed Collagen—Sources and Applications. 2019 November 7

Khatri M et al. The effects of collagen peptide supplementation on body composition, collagen synthesis, and recovery from joint injury and exercise: a systematic review. 2021 September 7

Li P et al. Roles of dietary glycine, proline, and hydroxyproline in collagen synthesis and animal growth. 2017 September 20

Nurilmala M et al. Characterization and Antioxidant Activity of Collagen, Gelatin, and the Derived Peptides from Yellowfin Tuna (Thunnus albacares) Skin. 2020 January 31

Nurilmala M et al. Characterization and Antioxidant Activity of Collagen, Gelatin, and the Derived Peptides from Yellowfin Tuna (Thunnus albacares) Skin. 2020 January 31

Lugo P et al. High glycine concentration increases collagen synthesis by articular chondrocytes in vitro: acute glycine deficiency could be an important cause of osteoarthritis. 2018 July 13

Bolke L et al. A Collagen Supplement Improves Skin Hydration, Elasticity, Roughness, and Density: Results of a Randomized, Placebo-Controlled, Blind Study. 2019 October 17

Bolke L et al. A Collagen Supplement Improves Skin Hydration, Elasticity, Roughness, and Density: Results of a Randomized, Placebo-Controlled, Blind Study. 2019 October 17

Song W et al. Identification and Structure–Activity Relationship of Intestinal Epithelial Barrier Function Protective Collagen Peptides from Alaska Pollock Skin. 2019 July 31

Hagemann V et al. Effects of 12 Weeks of Hypertrophy Resistance Exercise Training Combined with Collagen Peptide Supplementation on the Skeletal Muscle Proteome in Recreationally Active Men. 2019 May 14

Singh O et al. Collagen Dressing Versus Conventional Dressings in Burn and Chronic Wounds: A Retrospective Study. 2011 January to April

Liu B et al. The Use of Type I and Type III Injectable Human Collagen for Dermal Fill: 10 Years of Clinical Experience in China. 2005 August

López A et al. Hydrolyzed Collagen—Sources and Applications. 2019 November 7


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