Collagen supplements: the honest guide (2026)

Collagen supplements are food supplements that contain collagen, usually as hydrolysed collagen peptides from fish, cattle or pigs, sold as a liquid, powder or capsules. In the EU, no health claim has been authorised for collagen itself, so an honest guide is about what collagen is, where it comes from and how to compare products.

Below: the biology in plain language, how to read a label and what EU law allows sellers to say. No hype, no miracle promises.

What is collagen?

Collagen is a structural protein. Its long chains of amino acids twist into a triple helix, which makes it strong and hard to tear. You find it in your skin, bones, tendons, ligaments, cartilage and the walls of blood vessels.

Your body makes collagen itself, from the amino acids in the protein you eat. Glycine, proline and hydroxyproline are its typical building blocks. Vitamin C is needed for this process: vitamin C contributes to normal collagen formation for the normal function of skin, bones, cartilage, blood vessels, gums and teeth.

Does your body make less collagen as you get older?

Yes. Like many processes in the body, collagen production slows down gradually during adulthood. That is normal biology, and the pace differs from person to person.

Which types of collagen are there?

Scientists have described 28 types of collagen. Three of them matter most when you look at supplements: types I, II and III. Type I alone accounts for more than 90% of the collagen in your body.

A label that says "type I and III" usually means collagen from skin or hides. Type II almost always comes from cartilage.

Which foods contain collagen?

Collagen is found in the connective tissue of animals. Foods that naturally contain collagen or gelatine include:

• Bone broth: bones, joints and skin simmered for hours release collagen into the liquid as gelatine.
• Gelatine: cooked collagen, used in desserts, jellies and sweets.
• Fish skin, and the skin of chicken and pork.

Plants contain no collagen. Products sold as "vegan collagen" usually contain vitamin C, amino acids or plant extracts instead. How much collagen a food contains is rarely known.

What is hydrolysed collagen (collagen peptides)?

Whole collagen is a very large molecule. When it is heated, it turns into gelatine, which sets into a gel as it cools. When gelatine is broken down further with water and enzymes (hydrolysis), you get hydrolysed collagen, also called collagen peptides or collagen hydrolysate.

Collagen peptides are short pieces of the original protein. They dissolve in cold and warm drinks and do not gel. That is why almost every collagen supplement uses them. Some labels state the average peptide size in daltons (Da): a lower number means smaller pieces.

Marine or bovine collagen?

Marine collagen comes from fish, mostly the skin and scales, and is mainly type I. Bovine collagen comes from cattle hides, bones or cartilage and often contains types I and III. Fish is a major allergen, and bovine collagen does not suit pescatarians. Read the full comparison in marine or bovine collagen: what is the difference?

Liquid, powder or capsules: which form of collagen supplement suits you?

The collagen inside is much the same. The difference is mainly convenience, taste and how many grams you get per dose. There is no approved evidence that one form is absorbed better than another.

Want the details? Read liquid collagen, powder or capsules. Liquid Nefer makes liquid shots, such as Marine Beauty Collagen with 10,000 mg hydrolysed fish collagen types I and III per daily shot.

How do you read a collagen supplement label?

• Milligrams per daily dose. Look at the collagen per serving, not per bottle. 10,000 mg is 10 grams.
• Collagen type. Types I and III usually come from skin or hides, type II from cartilage.
• Source. Fish, bovine, porcine or chicken. This matters for allergies and dietary choices.
• Added vitamin C and other nutrients. Authorised claims on the pack belong to these vitamins or minerals, not to the collagen.
• Sugar and sweeteners. Check the ingredient list and the nutrition table.
• Allergens. In the EU, fish must be highlighted in the ingredient list.

To compare value, divide the price by the number of daily doses, then by the grams of collagen per dose. That gives you the price per gram of collagen, which is fairer than comparing bottle prices.

What does EU law say about collagen supplements?

In the EU, a health claim on a food may only be used once the European Commission has authorised it, based on a scientific assessment by EFSA. In 2011 EFSA assessed a claim for collagen hydrolysate and the maintenance of joints and concluded that a cause-and-effect relationship had not been established. The Commission refused that claim in 2012.

Today, no health claim for collagen is on the EU list of authorised claims. That is why responsible sellers do not promise effects on skin, joints, hair or ageing. Research on collagen is ongoing, but research is not an authorised claim. The claims about collagen formation that you see on packs belong to vitamin C, not to collagen.

Who should ask a doctor first?

Talk to your doctor or pharmacist before taking a collagen supplement if you:

• are pregnant or breastfeeding;
• take medication or have a medical condition;
• are allergic to fish, shellfish or another ingredient on the label;
• are buying for a child or teenager.

Never take more than the daily amount stated on the label.

Food supplements are not a substitute for a varied and balanced diet and a healthy lifestyle. This article is general information and not medical advice.