The two most common collagen sources are marine (from fish) and bovine (from cattle). Both are hydrolysed into peptides and both are widely used — but there are real differences worth understanding before you choose.
I'm Barry Lees, founder of The Health Improvers. This is educational buyer information, not medical advice or a health claim.
A quick note on claims
Whichever source you pick, remember that collagen itself doesn't carry an authorised health claim in the UK. The skin, hair and nail claims you'll see come from added nutrients like Vitamin C, Biotin and Zinc — not from the collagen. We explain that fully in our collagen, skin, hair & nails guide. Everything below is about source and quality.
Marine collagen
Sourced from fish skin and scales, marine collagen is predominantly Type I — the collagen most abundant in skin, hair, nails and bone. Its peptides are often noted for small particle size and good solubility. It suits pescatarians, and it's the usual choice for beauty-focused formulas. It isn't suitable for those avoiding fish, and it typically costs a little more.
Bovine collagen
Sourced from cattle, bovine collagen provides Types I and III together — a combination often associated with skin and structural tissue. It's usually more economical and widely available. It isn't suitable for vegetarians or those avoiding beef for dietary or religious reasons (look for Halal/Kosher certification if that matters to you).
Is one “better”?
Not really — they're different tools. Marine is prized for pure Type I and suits pescatarians; bovine gives you Types I and III at a friendlier price. Both should be hydrolysed peptides and provided at a meaningful dose (around 10g per serving is a good benchmark).
What actually matters more than the source
- Dose per serving — grams of collagen, not price per tub.
- Hydrolysed peptides for solubility and absorption.
- Added Vitamin C, Biotin, Zinc — the nutrients with the real claims.
- Source transparency and where it's made.
Our options
Our Marine Collagen is a pure hydrolysed Type I marine source, while our High Strength Collagen Peptides pairs 10g of collagen with Biotin, Zinc and Vitamin C. For the full picture, see our honest UK collagen buyer's guide.
Written by Barry Lees, founder of The Health Improvers. This article is for general information and education only. It is not medical advice and does not diagnose, treat or prevent any condition. Food supplements are not a substitute for a varied diet and healthy lifestyle. Always read the label.
Sources: peer-reviewed literature on collagen types and hydrolysed peptides; GB Nutrition and Health Claims Register; British Nutrition Foundation.
Explore more in our Joint, Skin & Beauty range.
0 comments