A claim is a promise with a file behind it. In the UK, cosmetic claims must be truthful, substantiated, honest and fair — and the evidence has to exist before the claim is printed, not after a complaint arrives.
The line you cannot cross
A cosmetic cleans, perfumes, changes appearance, protects, keeps in good condition. The moment a claim suggests treating, preventing or curing a disease, the product is a medicine, with an entirely different regulatory pathway and cost base.
| Wording | Problem | Defensible alternative |
|---|---|---|
| Treats rosacea or eczema | Disease claim | Formulated for sensitive, reactive skin — with tolerability data |
| Repairs DNA | Implies physiological repair | Supports the skin’s natural repair processes, with measured data |
| Boosts collagen | Usually unsubstantiated at the tested level | Clinically measured firmness improvement over eight weeks |
| Kills bacteria | Biocidal claim outside preservative function | Helps reduce odour-causing bacteria, where substantiated |
| Chemical-free | Impossible and misleading | Fragrance-free, silicone-free, formulated without… |
| Dermatologically tested | Meaningless without a defined protocol | Tested on 52 volunteers under dermatological control, with the report available |
Three tiers of evidence
- Ingredient rationale. Published literature or supplier data on an active. It justifies why an ingredient is there. It does not substantiate a product claim.
- Instrumental or in-vitro testing on your formula. Corneometry, TEWL, cutometry, image analysis. This is what supports a specific, measurable efficacy claim.
- Consumer perception studies. “92% agreed skin felt more comfortable after four weeks” is legitimate — provided the panel size, duration and question wording are documented and the figure is not extrapolated.
“Clinically proven” sits at the top of that ladder and requires a controlled study on the finished product, with a protocol a third party could repeat. If the study was run on an ingredient at 10% and your formula contains 1%, the claim is not supported.
Building a claim file
- The exact claim as it appears on pack, listed verbatim.
- The evidence relied on, with the report, date and laboratory named.
- The formula version tested, cross-referenced to the batch record.
- Panel details: size, age band, skin type, inclusion criteria, duration.
- Any qualification language used on pack (“in a consumer study of 54 participants”).
- A review date, because formulas and evidence age.
Where claims break
Three patterns account for most problems. The claim survives a reformulation that changed the active level. The claim was written by marketing and never reviewed against the file. The claim is technically true but implies something the evidence does not show — the “up to” construction being the classic example.
Write the claim you can evidence, then design the pack around it. The reverse order is how brands end up reprinting.
SPF, and why it is different
Sun protection claims require testing to a recognised standard and specific labelling. They also carry a heavier documentation burden and, in Great Britain, an ingredient annex that has recently changed. If SPF is on the front of the pack, the testing budget and timeline are not optional.
Read your top three claims and ask what document proves each one. If the answer is “the supplier’s brochure”, you have a rationale, not substantiation.
Where this sits in a real project
Claim review is part of the UK compliance route: the CPSR, the PIF and the label all have to say the same thing. The laboratory and documentation standards behind the evidence are described under quality and standards, and a claim that looks expensive to support is exactly the kind of question a paid feasibility review or an independent consultancy read should catch early.
Questions we are asked
What evidence do I need before printing a claim?
Evidence that exists before the claim is used, is relevant to the finished product at the stated concentration, and is held in the Product Information File. Claims must be truthful, substantiated, honest and fair; supplier ingredient stories on their own are not substantiation.
Can I rely on my ingredient supplier's data?
Supplier data supports the ingredient, not the finished formula or the concentration you used. It is a useful input, but instrumental or consumer testing on the locked formula is normally what makes the claim defensible to a retailer or an enforcement authority.
Why is SPF treated differently?
Sunscreen claims sit close to medicines regulation and carry specific efficacy and labelling requirements. A claim that implies protection or treatment rather than cosmetic appearance can move a product out of the cosmetic regime entirely, so we route those questions to a specialist before development.