Collagen is not one single ingredient. It is a family of structural proteins, and the three most common types in supplements, I, II and III, are built for different parts of the body.
Type I is the most abundant form and supports skin, bone, tendons and ligaments. Type II is found almost exclusively in cartilage, which is why joint products focus on it. Type III usually appears alongside type I in skin and blood vessel walls. Knowing which type matches your goal makes label reading much easier.
Collagen is a family, not one ingredient
Collagen makes up a large share of the protein in connective tissue throughout the body. There are more than two dozen recognized types, but supplements almost always focus on types I, II and III because these are the most abundant and the best understood.
Each type has a slightly different molecular structure suited to the tissue it supports. This is why a joint-focused collagen product looks different on the label than a skin-focused one, even though both say "collagen."
Type I: skin, bone, tendons and ligaments
Type I collagen is the most abundant type in the human body. It forms the structural framework of skin, bone, tendons, ligaments and scar tissue.
Supplements built around type I are typically marketed for skin and bone support, and they are usually sold as hydrolyzed collagen, meaning the protein has been broken into smaller peptides that are easier for the body to absorb. Common sources include bovine (cattle) hide and bone, and marine collagen from fish skin.
Type II: the cartilage-specific type used in joint products
Type II collagen makes up most of the collagen in cartilage, the smooth tissue that cushions joints. Because of this, it is the type used in supplements aimed at joint comfort and mobility rather than skin or bone.
Type II collagen supplements come in two main forms. Hydrolyzed type II is broken down like other collagen peptides. Undenatured type II keeps its natural structure and is typically used in much smaller amounts on the label. The two forms are not interchangeable, and a product will usually specify which one it contains.
Type III: the partner protein in skin and blood vessels
Type III collagen is often found working alongside type I, particularly in skin, blood vessel walls and other connective tissue. It is rarely sold on its own.
Most skin-focused collagen supplements combine type I and type III rather than listing type III separately, since the two occur together naturally in the body.
Comparing the three types at a glance
This table summarizes where each type is concentrated and what it is typically used for, to help you match a product to your goal.
| Type | Main tissue | Typical supplement form | Common goal on the label |
|---|---|---|---|
| Type I | Skin, bone, tendon, ligament | Hydrolyzed peptides (bovine or marine) | Skin and bone support |
| Type II | Cartilage | Hydrolyzed or undenatured | Joint comfort and mobility |
| Type III | Skin, blood vessels (with type I) | Combined with type I peptides | Skin support |
Reading the label and what to check
Once you know which type matches your goal, a few other label details are worth checking before you choose a product.
Look for a Natural Product Number (NPN) on the package. This means the product is licensed by Health Canada and has been reviewed for safety and label accuracy. You can also confirm a product's licence in the Licensed Natural Health Products Database.
Vitamin C is needed for the body to build its own collagen, so some products pair collagen peptides with vitamin C. This reflects how collagen is made in the body rather than a claim about the supplement itself.
- Check whether the label says type I, II or III, or a blend, and match it to your goal
- Note the source: bovine, marine (fish) or, less often, chicken cartilage for type II
- See if it is hydrolyzed (broken into peptides) or undenatured, especially for type II products
- Look for an NPN on the package
- Check for known allergens if you have a fish or shellfish allergy, since marine collagen is derived from fish
Who should ask a pharmacist first
Collagen supplements are generally well tolerated, but anyone who is pregnant, breastfeeding, giving a product to a child, or taking prescription medications should check with a doctor or pharmacist before starting a new supplement.
People with fish, shellfish or specific animal protein allergies should read the source ingredient carefully, since collagen can come from bovine, marine or poultry sources.
The short version
- Collagen supplements are not all the same, they are grouped by type based on which body tissue they match.
- Type I supports skin, bone, tendons and ligaments and is usually sold as hydrolyzed peptides.
- Type II is specific to cartilage and comes in hydrolyzed or undenatured forms for joint products.
- Type III usually appears combined with type I for skin support rather than sold alone.
- Check the label for type, source and an NPN, and ask a pharmacist if you are pregnant, breastfeeding or on medication.
Shop the products
Frequently asked questions
Can I take type I and type II collagen together?
Many people take separate products for different goals, such as a type I and III blend for skin and a type II product for joints, since they are usually sold separately. There is no known safety concern with taking both, but check with a pharmacist if you are combining several supplements.
Is marine collagen a different type than bovine collagen?
Marine and bovine collagen can both supply type I, they simply come from different sources, fish skin versus cattle hide or bone. Choose based on dietary preference or allergy concerns rather than assuming one source is a different type.
Why do some joint products list such a tiny amount of collagen?
This usually means the product contains undenatured type II collagen, which is used in much smaller amounts than hydrolyzed collagen because it works differently in the body. Check the label to see which form is listed.
Does taking collagen replace calcium or vitamin D for bone health?
No, collagen is a structural protein, not a source of calcium or vitamin D. For overall bone support, collagen is generally used alongside, not instead of, adequate calcium, vitamin D and vitamin K intake, which we cover in a separate guide on how those nutrients work together.
Keep reading
- Joint and Bone Supplements: What to Know Before You Buy
- Calcium Carbonate vs Calcium Citrate: Which One and When
- Calcium, Vitamin D and K2: How They Work Together
- Turmeric and Curcumin: Does Black Pepper Boost Absorption?
Sources
- NIH Office of Dietary Supplements: Vitamin C
- Health Canada: Licensed Natural Health Products Database
- Health Canada: About the Licensed Natural Health Products Database
- NCCIH: Using Dietary Supplements Wisely
This article is for general information only and is not medical advice. Talk to your doctor or pharmacist before starting a supplement, especially if you are pregnant or breastfeeding, take medication, or have a health condition.