If you've read a few collagen labels and come away more confused than when you started, you're not alone. Between "Type I," "Type II," "undenatured," "marine," and "hydrolyzed," it can feel like the label was written to be confusing on purpose.
Once you understand the different collagen types, and how that's different from the collagen "kind" a product is made from, the whole aisle stops feeling like a guessing game. Here's the plain-language version.
What Are the Different Types of Collagen?
There are actually 28 known types of collagen in the human body, but for supplements, only three really matter: Type I, Type II, and Type III. Each one has a different job and shows up in different tissues.
Think of your body like a house under construction. Type I is the framing and drywall, the dense structural material in your skin, bones, and tendons. Type II is the cushioning in a door hinge, specifically built for joints that need to move without grinding. Type III is the flexible mesh wiring behind the walls, working alongside Type I in places that need to stay both strong and stretchy, like blood vessels and skin.
"Type" vs. "Kind": Bovine, Marine, Hydrolyzed, and Bone Broth Explained
Here's where most of the confusion actually starts. Type I, II, and III describe what the collagen does in your body. Bovine, marine, hydrolyzed, and bone broth describe where it came from and how it was processed. They're two completely different classification systems, and marketing often blends them together like they're the same thing.
To make this concrete, here's which source tends to be rich in which type:
- Bovine collagen (from cattle hide and bone) is naturally rich in both Type I and Type III. We covered how it actually compares to marine sources in Marine vs. Bovine Collagen.
- Marine collagen (from fish skin and scales) is almost entirely Type I, with a slightly smaller peptide size on average.
- Chicken cartilage or eggshell membrane-derived collagen is where you'll find Type II, usually labelled "undenatured" or "UC-II" on the front of the bottle.
- Bone broth naturally contains a mix of Type I, II, and III, but in amounts that vary from batch to batch since it isn't a standardized process. We wrote more about that variability in Collagen Peptides vs. Bone Broth.
"Hydrolyzed" isn't a source at all, it's a processing step. It means the collagen has been broken down into smaller peptides for easier absorption, and it can be applied to bovine, marine, or Type II collagen alike. So a product can be "hydrolyzed bovine Type I collagen" all at once, that's three separate pieces of information stacked together, not three competing choices.
Type I Collagen: The Body's Main Building Block
Type I makes up around 90% of the collagen in your body, so when people talk about collagen supplements generally, they're usually talking about Type I. It forms dense, tightly packed fibres that give your skin its firmness, your bones their structure, and your tendons their strength.*
Once Type I is built, it tends to stick around rather than being replaced quickly, which is part of why supporting its production becomes more relevant as you get older and natural collagen turnover slows down.* If you're looking at a general collagen powder for skin, hair, or nails, Type I is almost always the one doing the work.
Type II Collagen: The One Joints Actually Need
Type II collagen is a different structure entirely, thinner fibres arranged in a loose, springy mesh instead of dense sheets. That structure is exactly what cartilage needs to cushion your joints and absorb impact.*
This is the type behind the "undenatured collagen type II" and "UC-II" searches you'll see, since undenatured simply means the collagen has kept its original molecular shape rather than being broken down the way hydrolyzed collagen is. If joint comfort is specifically what you're after, Type I alone won't target that the way Type II does. It's worth checking the label for Type II or UC-II by name rather than assuming any collagen powder covers joints.*
Type III Collagen: Type I's Flexible Partner
Type III almost always shows up alongside Type I, in your skin, blood vessels, and intestinal walls, rather than as its own separate ingredient. Where Type I provides the dense structure, Type III adds flexibility, forming thinner, branching fibres that let tissue stretch and bounce back.*
Because it's naturally paired with Type I in the body, most collagen powders that support skin health include both together rather than isolating Type III on its own. That's also why bovine collagen, which is naturally rich in both, tends to be the more common choice for general skin, hair, and nail support.
Which Collagen Type Is Right for Your Goal?
If your main goal is skin, hair, or nail support, look for Type I, or a bovine or marine source, since both are naturally Type I-rich. If joint comfort is the priority, look specifically for Type II or UC-II on the label rather than assuming a general collagen powder covers it.* If you want broad, general support and aren't targeting one specific goal, a Type I and III blend, like what you'll find in most bovine collagen peptide powders, covers the most ground.
Do You Need One Type, or All Three?
For most people focused on skin, hair, nails, or general wellness, a Type I and Type III blend is enough, and it's what a lot of everyday collagen peptide powders are built around. You don't need all three types unless you're specifically trying to support joints alongside general collagen production, in which case combining a Type I/III product with a dedicated Type II or UC-II supplement covers more ground than either alone.
There's no harm in taking a product with all three, but there's also no need to feel like you're missing something if yours only covers one or two. It comes down to matching the type to your actual goal rather than assuming more types automatically means a better product.
Frequently Asked Questions
Q: What's the difference between collagen types 1, 2, and 3?
Type I supports skin, bone, and tendon structure and makes up about 90% of the body's collagen. Type II is specific to cartilage and joint cushioning. Type III works alongside Type I in skin, blood vessels, and intestinal walls, adding flexibility to Type I's structure.
Q: Is undenatured (UC-II) collagen better for joints?
If joint comfort is your specific goal, Type II or UC-II collagen is the more targeted choice, since it's the type actually found in cartilage. A general Type I collagen powder isn't built for that same purpose, even though it may still support skin, hair, and nails.*
Q: Which collagen type is best for skin?
Type I is the main one, since it makes up most of your skin's structural collagen, usually alongside Type III for added elasticity. Bovine and marine collagen sources are both naturally rich in Type I, which is why they're the most common choices for skin-focused products.
Q: Do I need more than one collagen type?
Not necessarily. Most people focused on skin, hair, nails, or general wellness are well covered by a Type I and III blend. Type II is only worth adding specifically if joint support is a goal on its own.
The Bottom Line
Type I, II, and III collagen aren't competing products, they're different tools for different jobs. Type I builds structure, Type II cushions joints, and Type III adds flexibility alongside Type I. Once you separate that from the bovine, marine, hydrolyzed, and bone broth conversation, which is really about source and processing, not function, choosing a collagen supplement gets a lot simpler.
If you want to see the options side by side, you can browse our full collagen collection, or reach out to our team. We're happy to help you match a type to what you're actually trying to support. If you're deciding between a specific product, our Designs for Health Whole Body Collagen review is a good place to see how one holds up in real use.
