Collagen
Collagen, biotin or zinc: which details help you compare?
AI-generatedIf you're standing in front of a shelf of beauty supplements, you usually compare two numbers on the front. This guide shows which details on the back actually help.
Why beauty products are hard to compare
The front of a pack shows a big word and a big number: "Collagen 10,000 mg", "with biotin", "plus zinc". Yet two products with the same wording can be composed very differently – in the amount of collagen, in the micronutrients they contain and in their dosage.
For an honest comparison, you need three details that must appear on every pack:
- the recommended daily portion;
- the amount of each nutrient per daily portion – for vitamins and minerals, also as a percentage of the NRV;
- the complete list of ingredients.
Putting the NRV in context: The EU nutrient reference value (NRV) is a reference value for labelling for adults. It is neither an individual intake recommendation nor a safety upper limit. 2
More in our guide Vitamins and minerals: requirements, intake and overdosing.
Collagen: which details are meaningful
Collagen is a protein – no NRV has been set for collagen. Instead, the meaningful details are:
- the amount of collagen per recommended daily portion (not the net quantity of the pack);
- the animal source and, if applicable, the collagen type;
- the branded raw material used, including the raw material manufacturer, if stated.
Important for context: no authorised health claim is listed in the EU Register for collagen itself. For claims submitted in the past, EFSA did not confirm a sufficiently established cause-and-effect relationship either for collagen hydrolysate and joints or for a change in skin elasticity. If an authorised claim appears on a collagen pack, it refers – provided the respective conditions of use are met – to the micronutrients it contains. 345
More on the evidence in our guide: Collagen: effects, intake, duration and possible risks.
Biotin: small reference value, high percentages
The EU nutrient reference value for biotin for adults is 50 µg. Because this reference value is small, even low absolute amounts can lead to high % NRV figures. A higher percentage is not automatically better; % NRV is not a measure of a stronger effect. 2
For biotin, the following claims, among others, are authorised, provided the specific product meets the legal conditions of use: 1
Biotin contributes to the maintenance of normal hair.
Biotin contributes to the maintenance of normal skin.
In the EU Register, there is no authorised claim for biotin on the maintenance of normal nails. Corresponding authorised claims exist for zinc and selenium – in each case only if the legal conditions of use are met. 5
Zinc: authorised claims on hair, skin and nails
The EU nutrient reference value for zinc for adults is 10 mg. For zinc, the following claims, among others, are authorised, provided the specific product meets the legal conditions of use: 12
Zinc contributes to the maintenance of normal hair.
Zinc contributes to the maintenance of normal skin.
Zinc contributes to the maintenance of normal nails.
Zinc can be contained in several products you use at the same time, for example in a collagen product, a multivitamin and a single zinc supplement. When combining products, you should therefore take into account the total intake from all the food supplements you use.
Selenium: authorised claims on hair and nails
Selenium can be part of a multi-nutrient formula, for example alongside vitamin C, zinc and copper. The EU nutrient reference value for selenium for adults is 55 µg. The NRV is a labelling value and not an individual intake recommendation or maximum level. 2
For selenium, the following claims, among others, are authorised, provided the specific product meets the legal conditions of use: 1
Selenium contributes to the maintenance of normal hair.
Selenium contributes to the maintenance of normal nails.
No authorised claim on the maintenance of normal skin is listed for selenium. When comparing biotin, zinc and selenium, the corresponding skin claims refer to biotin and zinc. Selenium can also be contained in several products used at the same time; the total intake from all the food supplements you use should therefore be taken into account. 5
Vitamin C: the only authorised link to collagen
There is no authorised claim for collagen itself. But there is one for vitamin C, and it explicitly refers to the body's own collagen formation:
Vitamin C contributes to normal collagen formation for the normal function of skin.
This claim concerns collagen formation in the body. It says nothing about what happens to collagen peptides you consume. The EU nutrient reference value for vitamin C for adults is 80 mg; the claim may be used if the product provides at least 15% of it per daily portion.
How to compare in practice
- Use the recommended daily portion as the basis for comparison – not the pack size and not the number on the front.
- For each product, note the amount of collagen per recommended daily portion.
- For each micronutrient, note the amount and the % NRV per daily portion.
- Read the complete list of ingredients – sweeteners, flavourings and colourings are listed there too.
- Separate authorised claims (recognisable by the wording "contributes to …") from general advertising language.
- Finally, check your total intake across all the food supplements you already use.
How to find the details on the pack is shown in our guide Reading labels correctly; why the daily portion counts is explained in Per capsule or per daily dose?
And finally, a realistic basic rule:
In your beauty routine too, what matters is the recommended daily portion, the amount of each nutrient and the complete list of ingredients.
Mandatory notices: Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle. Do not exceed the stated recommended daily dose.
An example from the SteloSupps range
How the details discussed above appear on a real pack is shown by COLLAGEN BEAUTY by NaturWelle. Declared per recommended daily portion: vitamin C 100 mg (125% NRV), zinc 10 mg (100% NRV), selenium 55 µg (100% NRV), copper 1 mg (100% NRV), biotin 30 µg (60% NRV), plus 10,000 mg of collagen peptides and 75 mg of hyaluronic acid.
The authorised claims mentioned above each refer to the individual nutrient and require that its condition of use is met. No health claim is authorised in the EU Register for collagen peptides or hyaluronic acid; both are mentioned here solely as part of the composition.
More guidance in our guide:
Frequently asked questions
Does collagen have an authorised health claim?
No. No authorised health claim is listed in the EU Register for collagen itself. Claims about skin, hair or nails refer – provided the respective conditions of use are met – to the micronutrients it contains.
Why can a biotin pack state several hundred percent NRV?
The EU nutrient reference value for biotin for adults is 50 µg. Even low absolute amounts can therefore lead to high percentages. A higher percentage is not automatically better; % NRV is not a measure of a stronger effect.
Is there an authorised biotin claim for nails?
No. In the EU Register, there is no authorised claim for biotin on the maintenance of normal nails. Corresponding authorised claims exist for zinc and selenium – in each case only if the legal conditions of use are met.
Which of the ingredients compared here have an authorised claim on skin?
Corresponding authorised claims exist for biotin and zinc, provided the respective product meets the legal conditions of use: "Biotin contributes to the maintenance of normal skin." "Zinc contributes to the maintenance of normal skin." For selenium, there are authorised claims on the maintenance of normal hair and nails, but not on the maintenance of normal skin. No authorised health claim is listed in the EU Register for collagen itself.
What should I watch out for when combining several beauty products?
The total intake of the same vitamins and minerals across all the food supplements you use – several products that are each correctly dosed can together provide unnecessarily high amounts.
Does a beauty supplement replace a balanced diet?
No. Food supplements supplement the diet; they don't replace it.
Why do collagen products often list vitamin C on the pack?
Because there is an authorised claim for vitamin C on the body's own collagen formation, but none for collagen itself. The claim refers to the vitamin, not to the collagen peptides contained.
Sources
Sources as of: 22 September 2026.
- EU Register / Regulation (EU) No 432/2012 – authorised health claims
- Regulation (EU) No 1169/2011, Annex XIII – reference intakes (NRV) for vitamins and minerals
- EFSA Journal (2011): Collagen hydrolysate and maintenance of joints
- EFSA Journal (2013): VeriSol®P and a change in skin elasticity
- EU Register of Nutrition and Health Claims
