Collagen supplements: which form, which dose, and what the studies actually measured

Need guide · Skin at Health Royals · 8 min read

Collagen is the most sold and least explained ingredient in beauty. The word on the label tells you almost nothing. The form, the dose and the study behind it tell you everything.

Why skin behaves differently after forty

The usual description is that skin gets drier. That is true but incomplete, and the incompleteness is why so many products disappoint.

Three things change at once, and they are not the same thing.

Structure. Collagen turnover slows. Collagen is the scaffolding of the dermis, and when it is renewed more slowly the skin loses some of its firmness and bounce.

Water. Hyaluronic acid levels in the dermis fall. Hyaluronic acid is central to the water-rich environment around skin cells, so less of it means a drier environment beneath the surface, not only on it.

Barrier. The lipid barrier that limits water loss becomes less efficient, so whatever moisture is there escapes faster.

A cream works mainly on the third of those, from the outside. That is a real contribution, and it is also why a cream alone can feel like it is not enough.

Dry skin is rarely only a surface problem. It is usually structure, water and barrier changing together.

Can collagen survive being eaten?

This is the honest objection, and it deserves an honest answer rather than a marketing one.

Collagen is a protein. Like other proteins it is broken down during digestion into smaller pieces: peptides and amino acids. It does not travel intact to the skin, and anyone who implies otherwise is describing something that does not happen.

What research has examined is different. Certain collagen peptides can be absorbed and appear in circulation, and studies have looked at whether a daily intake of a specific peptide preparation is associated with measurable changes in skin properties over time.

That is a narrower question than most collagen marketing suggests, and it is the only one worth answering.

The interesting question is not whether collagen reaches the skin whole. It is what a defined daily amount of a defined preparation was measured to do.

Type I, II and III: why the number matters

Collagen comes in several types, distributed differently through the body.

Type I is the most abundant type in skin and bone. Type II is the dominant type in cartilage. Type III occurs alongside type I in skin and blood vessels.

Most collagen supplements on the market use type I and III from bovine or fish sources, usually as hydrolysed peptides.

Beauty Complete™ uses Cartidyss®, a marine type II collagen complex. That is a deliberate and slightly unusual choice, and it comes with an obligation to explain it rather than assume the number impresses anyone.

Cartidyss® is not isolated collagen alone. It is a complex that also carries naturally associated glycosaminoglycans, the family of molecules that includes hyaluronic acid and chondroitin.

The type tells you where that collagen belongs in the body. The named raw material tells you what was actually studied.

Marine or bovine?

A question we are asked often, and the answer is less dramatic than the internet suggests.

Marine collagen is derived from fish or other marine sources. Bovine collagen is derived from cattle. Both can be processed into peptides. Neither is inherently superior as a category.

What differs in practice is source traceability, the type profile, whether the material suits particular dietary preferences, and, most importantly, whether that specific preparation has been examined in human research.

We chose a marine source for Cartidyss® for traceability and formulation reasons, not because marine collagen is a better category than bovine collagen. We would rather say that plainly than invent a hierarchy.

Source is a real consideration. It is not the deciding one. The deciding one is what was studied, at what amount.

What the research on Cartidyss® examined

Published work on Cartidyss® examined a daily intake of 500 mg over 90 days and measured skin-related outcomes including wrinkle-related measures and dermal density.

Beauty Complete™ provides that same 500 mg per daily dose.

The trial was run on the raw material Cartidyss®, in 46 women aged 45 to 59, at exactly the amount that sits in Beauty Complete™. That is how we choose raw materials: a defined ingredient, a defined amount and a published trial you can look up.

The full write-up is here: marine collagen for skin, and what makes Cartidyss® different.

Naming the raw material, the amount and the duration is what makes a statement checkable. Vague collagen claims are unfalsifiable by design.

The other two thirds: water and barrier

Collagen addresses structure. It does nothing for the other two changes, which is why a collagen-only product is an incomplete answer to a three-part problem.

Each has its own write-up: hyaluronic acid and ceramides.

Alongside them, vitamin C contributes to normal collagen formation for the normal function of skin, and biotin and vitamin B2 contribute to the maintenance of normal skin. Those are authorised claims and we state them as written. More on vitamin C and collagen formation.

Beauty Complete™

Two capsules a day. Formulated so that structure, water and barrier are addressed together rather than one at a time.

Go deeper

• Marine collagen for skin: what makes Cartidyss® different
• Oral hyaluronic acid for skin: the research behind Hyabest®
• Ceramides for skin: the barrier research behind Ceramosides™
• Vitamin C and collagen formation
• Skin health: the living foundation of beauty
• Branded versus non-branded ingredients
• Menopause and midlife: what changes in the body

Frequently asked questions

Powder or capsule?
A powder is measured in scoops and grams of a collagen that rarely has a name, a type or a molecular weight stated. Beauty Complete™ is measured in milligrams of a characterised, studied raw material, in a capsule that protects it from air and moisture, so the amount in the capsule can be compared with the amount in the trial. Our view is explained here.

Is 500 mg not very little compared with a 10 g scoop?
It is a smaller number, and comparing the numbers alone is misleading. A gram figure for an unspecified peptide mixture and a milligram figure for a characterised complex studied at that exact amount are not the same kind of information.

Does it work for joints?
Type 2 collagen comes from cartilage, which is why the question comes up. Cartidyss® is a hydrolysed fish cartilage in which the chondroitin sulphate comes along. The trial on the raw material measured skin, and that is what we build on. Persistent joint pain belongs with a doctor.

How long before anything is measurable?
The published research on Cartidyss® ran over 90 days. Skin renews on its own timescale, and twelve weeks is the shortest sensible period over which to judge anything.

Is it suitable if I avoid fish?
No. Cartidyss® is a marine-derived ingredient.

Important information

This page is general information and educational reading. It is not medical advice, and it does not diagnose or treat any condition. Food supplements are not a substitute for a varied diet and a balanced lifestyle. Individual needs and experiences vary. Research described here was conducted on individual ingredients, not on the finished product. If you are pregnant, breastfeeding, taking medication, have allergies or have a medical condition, speak to a qualified healthcare professional before taking a supplement.