Cosmetics efficacy testing to support product claims

Published January 5, 2024

Commission Regulation (EU) No 655/20131 lays down the criteria for cosmetic product marketing claims. The six key principles that all claims should respect are legal compliance, truthfulness, evidential support, honesty, fairness, and informed decision-making.

To comply with the criteria, cosmetics manufacturers should generally produce evidence from experimental studies or consumer perception tests to support the claims they wish to make about their product’s effectiveness and tendency to be well-tolerated by consumers.

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What do the criteria for cosmetic product claims mean in practice?

The European Commission elaborates on each product claim criterion in a separate technical document2, which also provides examples of the types of claims that are not acceptable:

  • Legal compliance: Product claims must not be based on mere compliance with the law, as all cosmetics sold in the EU must be compliant. For example, the absence of a prohibited chemical cannot be the basis of a marketing claim.

  • Truthfulness: Product claims must not be based on false or irrelevant information. For example, cosmetics must contain the ingredients described or prominently displayed on the packaging, not just the flavors or aromas of such ingredients.

  • Evidential support: The manufacturer must produce appropriate scientific evidence to substantiate claims about the cosmetic product’s efficacy. Common ways to do this include experimental studies and consumer perception tests.

  • Honesty: Claims about the product’s effectiveness must not go beyond the supporting evidence. For example, sales figures are not to be considered customer endorsements.

  • Fairness: Competitors should not be denigrated for the use of legal ingredients. A product’s effectiveness must also not be compared to another product with a different function.

  • Informed decision-making: Claims must be relevant, clear, and precise enough to be understood by the intended end user, whether a regular consumer or a cosmetics industry professional. 

Evidencing product claims: best practices for testing

Experimental studies and consumer perception tests are the industry standard for generating evidence to support cosmetic product efficacy claims. In experimental studies, the effects of the product are either observed by a professional, such as a dermatologist or dentist, or measured using purpose-built testing equipment. Consumer perception tests, on the other hand, are based on questionnaires that volunteers fill in after using the product. Both approaches can also be incorporated into one study.

Regardless of the chosen approach, the methods used should be reliable and reproducible, and all studies should be conducted by appropriately qualified personnel. There should also be enough participants to yield statistically significant results. When consumer perception is assessed, careful attention must be paid to the wording of the questionnaire to ensure that responses are reliable.

Examples of testing options

Table 1 summarizes some of the most commonly performed cosmetic product efficacy tests and the claims they can be used to support. All of the tests are performed with human volunteers, as testing cosmetics with animals is prohibited in the EU.

Table 1: Tests to support cosmetics efficacy claims

Claim or claims

Suggested study

Example of study design

“Dermatologically tested”

Patch test or HRIPT (human repeat insult patch test)

48-hour exposure to the product, reactions observed by a dermatologist

“Moisturizes the skin”

“Reduces the feeling of tightness and dryness”

“Restores the function of the skin barrier”

Moisturizing efficacy test

Product used for 7 days, moisturizing effect measured with Corneometer® CM 825 + self-assessment questionnaire

“Decreases TEWL (transepidermal water loss)”

TEWL test

Water evaporation from the skin measured before and after use with Tewameter® TM 300

“Lightens discoloration”

“Evens the skin tone”

“Reduces skin redness”

Skin redness & melanin level test

Melanin and redness levels measured before and after use with Mexameter® MX 18

“Improves skin elasticity”

“Improves skin firmness”

Biomechanical skin parameter test

Firmness and elasticity measured before and after use with Cutometer® MPA 580

“No tears”

“Does not sting the eyes”

No tears test

Diluted product dropped in volunteers’ eyes, eye examination by an ophthalmologist and self-evaluation of irritation

The study design can be modified in terms of the number of participants and their characteristics, such as skin type. For example, volunteers with sensitive skin can be used in patch tests to support additional claims, such as “suitable for sensitive skin”.

Claims related to sunscreen products

The European Commission provides additional, more specific requirements for claims relating to the efficacy of sunscreen products, as there is a high risk of damage to consumer health if such products are marketed misleadingly.3 Claims about the sun protection factor (SPF) should be supported by evidence acquired through standardized, reproducible tests accounting for both UVA and UVB radiation. The critical wavelength, up to which the product protects the user from 90% of radiation, should also be determined.

Standardized testing options for UVA and UVB protection factor determination include ISO 24443 and ISO 24444, respectively. Depending on the results, sunscreen products can be labeled with the sun protection factors outlined in Table 2. A category (low, medium, high, or very high) for the protection efficacy should also be provided on the product label.4

Table 2: Sun protection factor labeling by EU recommendations


Declared SPF

Measured SPF

Low protection

6 or 10

6-9.9 or 10-14.9

Medium protection

15, 20, or 25

15-19.9, 20-24.9, or 25-29.9

High protection

30 or 50

30-49.9 or 50-59.9

Very high protection



Cosmetics efficacy testing by EU regulations and guidelines

Measurlabs offers a range of cosmetics testing options for determining the sun protection factor of sunscreen products and for evaluating the efficacy and skin tolerance of all types of cosmetics. Do not hesitate to contact us through the form below or at to request a quote. Please provide a comprehensive description of the product, the claims you wish to test, and the study design you wish to use. All of these factors affect the pricing, as the tests are always tailored to your product’s specifications.


1 Commission Regulation (EU) No 655/2013 laying down common criteria for the justification of claims used in relation to cosmetic products

2 European Commission’s Technical document on cosmetic claims

3 Commission Recommendation C(2006) 4089 on the efficacy of sunscreen products and the claims made relating thereto

4 The table is based on the table in Section 4 of Commission Recommendation C(2006) 4089.

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Measurlabs offers a wide range of tests for evidencing skin tolerance and efficacy claims.

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  • What kind of cosmetic product do you have?

  • Which claim(s) do you wish to test?

  • What are the requirements for study design (number of participants, skin types, etc.)?

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