Why the Sea Became a Source of Collagen

Marine collagen is almost always sourced from fish, but why? Discover where fish collagen comes from, how it is produced and why understanding its origin matters.

Marine collagen has become one of the best-known forms of collagen supplementation, especially among people interested in skin health and healthy ageing. While many people recognise the name, fewer know why fish are used in the first place.

The answer begins with collagen itself.

Fish naturally contain large amounts of collagen within their connective tissues. Rather than allowing these tissues to go unused after food production, they can be processed into collagen peptides that are suitable for nutritional supplements.

Understanding why fish are used for marine collagen helps explain not only where the ingredient comes from, but also why transparency and evidence matter more than marketing claims.

What is marine collagen?

Collagen is the most abundant structural protein in the human body. It helps provide strength and support to skin, bones, tendons, ligaments and connective tissues.

Scientists have identified at least 28 different collagen types. Marine collagen is naturally rich in Type I collagen, which is also the most abundant collagen found in human skin.

Most marine collagen supplements contain hydrolysed collagen peptides, meaning the collagen has been broken into smaller protein fragments that dissolve easily and have been widely studied in human research.

Why are fish used?

Fish are used because several of their tissues naturally contain high concentrations of collagen.

These commonly include:

- skin

- scales

- bones

- connective tissues

After the edible portions of the fish have been processed for food, these collagen-rich tissues can be used to produce marine collagen rather than being discarded.

This approach makes use of naturally occurring collagen already present within the fish.

The exact fish species used varies between manufacturers.

How is fish collagen turned into supplements?

The collagen found in fish tissues is first extracted and purified.

It is then hydrolysed, a process that breaks large collagen proteins into much smaller collagen peptides.

Hydrolysed collagen dissolves more easily in liquids and has become the form most commonly investigated in scientific studies.

Although manufacturers may use different production methods, the overall goal remains similar: producing purified collagen peptides suitable for nutritional use.

Are fish the only source of collagen?

No.

Collagen supplements can also be produced from cattle, pigs and chickens.

The difference is largely one of origin.

Marine collagen is naturally rich in Type I collagen, while bovine collagen commonly contains Types I and III, and chicken collagen contains higher amounts of Type II collagen.

Current research has not shown that one source is universally superior for everyone. Instead, the choice often depends on dietary preferences, allergies and personal values.

What does the science say?

Strong evidence

Several systematic reviews and meta-analyses suggest that oral hydrolysed collagen supplementation may improve measures of skin hydration and skin elasticity in healthy adults.

Researchers continue to investigate the biological mechanisms behind these observations, but current evidence supports collagen peptides as a promising area of nutritional research.

Limited evidence

Studies have explored collagen supplementation for:

- joint comfort

- nail strength

- hair appearance

- exercise recovery

While some results are encouraging, larger independent clinical trials are still needed.

Early evidence

Researchers continue studying whether collagen source, peptide size or manufacturing methods influence health outcomes.

At present, evidence remains limited, and further high-quality human studies are required.

Not yet proven

Current evidence does not demonstrate that:

- fish collagen is always better than every other collagen source

- all marine collagen products are identical

- collagen supplements reverse ageing

- marine collagen guarantees visible skin improvements

- source alone determines supplement quality

These claims go beyond the available scientific evidence.

How may marine collagen fit into a daily routine?

People who choose collagen supplements often add hydrolysed collagen powder to coffee, smoothies, yoghurt or porridge because it mixes easily and has a relatively neutral taste.

Whether someone chooses marine collagen, bovine collagen or another source is a personal decision that should sit alongside a balanced diet and healthy lifestyle.

What should you look for?

When comparing marine collagen supplements, consider looking for:

- hydrolysed collagen peptides

- complete ingredient lists

- transparent sourcing information where available

- allergen advice

- realistic health claims

- evidence-based communication

Clear information is often more valuable than impressive marketing language.

Safety

Marine collagen is generally considered well tolerated for most healthy adults.

People with fish allergies should avoid marine collagen products unless advised otherwise by a qualified healthcare professional.

Anyone who is pregnant, breastfeeding, taking prescription medicines or living with a medical condition should seek personalised medical advice before starting supplements.

Frequently Asked Questions

Why is marine collagen made from fish?

Fish naturally contain collagen-rich tissues such as skin, scales and bones, making them a suitable source for collagen extraction.

Is all fish collagen the same?

No. Fish species, processing methods and manufacturing standards vary between producers.

Is fish collagen different from bovine collagen?

Yes. Marine collagen is naturally rich in Type I collagen, while bovine collagen typically contains both Types I and III.

Can vegetarians take marine collagen?

No. Marine collagen is an animal-derived ingredient obtained from fish.

Does fish origin guarantee quality?

No. Transparency, manufacturing standards and evidence-based communication are all important factors alongside ingredient origin.

A better understanding of marine collagen

Fish are used for marine collagen because they naturally contain collagen-rich connective tissues that can be carefully processed into collagen peptides. This makes marine collagen one of several available sources of collagen supplementation, each with its own characteristics.

Understanding why fish are used helps move the conversation beyond simple marketing claims. Looking for transparency, realistic information and research-backed communication allows consumers to make informed decisions based on evidence rather than assumptions.

References

1. de Miranda RB, Weimer P, Rossi RC. Effects of hydrolyzed collagen supplementation on skin aging: a systematic review and meta-analysis. International Journal of Dermatology.

2. <https://pubmed.ncbi.nlm.nih.gov/33742704/

3. Pu SY, et al. Oral collagen supplementation for skin health: A systematic review and meta-analysis. Nutrients. 2023. <https://pubmed.ncbi.nlm.nih.gov/36986257/

4. NIH MedlinePlus. Collagen. <https://medlineplus.gov/

5. World Health Organization. Healthy Diet. <https://www.who.int/news-room/fact-sheets/detail/healthy-diet