Ad description
A poster ad for Eucerin Skincare, seen at Balham Underground station on 18 November 2025, featured a photo of a woman’s face with dots highlighting an area of her cheek.
Text stated. “Eucerin LOOK UP TO 5 YEARS YOUNGER* RECOMMENDED BY DERMATOLOGISTS”. The ad included an image of the Eucerin Hyaluron-Filler Epigenetic Serum product and text beside it stated “CLINICALLY PROVEN”. Smaller text stated, “*Product-in-use test over 4 weeks with 160 volunteers.”
Issue
The complainant challenged whether the claim “LOOK UP TO FIVE YEARS YOUNGER” was misleading and could be substantiated.
Response
Beiersdorf UK Ltd t/a Eucerin said the claim “LOOK UP TO FIVE YEARS YOUNGER” was substantiated by a study that involved 160 participants who used the product for four weeks. After four weeks, they were asked how much younger they thought they looked compared to before they started using the product. They presented the claim as “up to” to reflect a genuine maximum rather than a typical result.
They said that the claim referred strictly to perceived age, which was inherently subjective. The study relied on consumer self-assessment, which was an industry-standard method for evaluating appearance-related cosmetic claims. They said that the claim did not refer to any clinically measured or biological change in age, and that the basis for the claim was made clear in the ad with the on-screen text “Product-in-use test over 4 weeks with 160 volunteers”.
They also provided three further studies and one peer-reviewed research paper, which were conducted by independent research institutes and Beiersdorf research teams. Beiersdorf UK stated that these studies contained supporting information but did not directly substantiate the claim.
Assessment
Upheld
The CAP Code stated that before distributing or submitting a marketing communication for publication, marketers must hold documentary evidence to prove claims that consumers were likely to regard as objective and that were capable of objective substantiation. Objective claims must be backed by evidence, if relevant, consisting of trials conducted on people.
The ad showed a woman with an area of her face highlighted. Large wording on the poster stated “LOOK UP TO 5 YEARS YOUNGER*” and smaller text stated “*Product-in-use test over 4 weeks with 160 volunteers”. Text beside an image of a bottle of the serum stated “CLINICALLY PROVEN”. We considered viewers were likely to understand the headline claim to mean that the product was clinically proven to improve the appearance of skin such that it noticeably could give a more youthful appearance of up to five years younger. We considered that the claim to look up to five years younger was capable of objective substantiation, and we therefore expected to see evidence to demonstrate that was the case.
We reviewed the evidence provided, which comprised four studies and one peer-reviewed research paper. Beiersdorf UK requested that we treat the specific details of some of the studies as confidential, because they contained commercially sensitive information.
The first study, which was referred to in the qualifying text in the ad, was unpublished and examined the effect of 4 weeks’ use of the serum in 160 participants. After four weeks, they were asked if they thought they looked younger compared to before they used the product and if so, by how many years. We had concerns about the study’s methodology, including that there was no control group, nor was there information about how participants were recruited. Additionally, although the report described the study as blind, it did not explain who was blinded (for example: participants, investigators, assessors), or how the blinding was maintained. We considered that, although the report stated that participants used the product at least 4–5 times per week, it did not provide a detailed protocol such as a standardised application amount or restrictions on using other skincare, and other inclusion or exclusion criteria, which may have
influenced the results.
Additionally, whilst we acknowledged that there was a high level of agreement to the question of whether the product helped them look younger, we considered that the results were self-reported and subjective, and therefore not sufficiently robust to substantiate the clinically proven claim to look up to five years younger.
We also considered the relevance of the trial conditions to typical UK use. We understood that the trial was conducted in a country with a hotter, sunnier climate than the UK and different participant characteristics in terms of skin type. We did not receive information regarding the range of skin types included in the study. We considered that the differences that could arise from climate and participant characteristics may reduce the extent to which the results could be taken as directly representative of typical use by UK consumers in everyday conditions. For those reasons, we considered that the study was not sufficiently robust to substantiate the claim “LOOK UP TO FIVE YEARS YOUNGER”.
We next considered the further studies Beiersdorf UK provided for supporting context. The second study was unpublished and assessed the serum’s effects on biological skin age. Whilst the study used an objective measure, we considered there were limitations with the study’s design, including that there was no control group, nor were participants or those involved in running the study blinded to the treatment. Notwithstanding this, the results only showed a reduction of one year in biological skin age after 4 weeks, which did not substantiate the claim to look up to five years younger. The study also included a questionnaire. We noted that participants reported an average reduction of 5 years after 4 weeks using the serum, however, we considered that these results were subjective and self-reported, and therefore were not sufficiently robust to substantiate a “clinically proven” claim.
The third study was unpublished and did not include any measurement to quantify the anti-ageing effect the product had. We therefore considered that it was not relevant to substantiate the claim.
The fourth study was unpublished and involved asking a large cohort of women questions about the perceived skin benefits after 4 weeks of using the serum, including whether they agreed with the statement that they looked up to 5 years younger. We had concerns with the study methodology, including that there was no control group, and limited information provided about how the study was carried out in terms of participant recruitment and blinding. We considered that because the results were subjective and self-reported, the study was not sufficiently robust to substantiate a “clinically proven” claim.
The fifth study was a published, peer-reviewed study, that looked at the rejuvenating activity of the active ingredient used in the serum on skin. However, we considered that because the study did not include the advertised product, nor looked at the daily use of the product and the effect it had on improving the youthfulness of the skin, it was not sufficient to substantiate the claim.
Therefore, because we had not seen sufficient evidence to substantiate the claim that the serum was clinically proven to give a more youthful appearance of up to five years within four weeks, we concluded that the claim was misleading.
The ad breached CAP Code (Edition 12) rules 3.1 (Misleading advertising), 3.7 (Substantiation) and 12.1 (Medicines, medical devices, health-related products and beauty products).
Action
The ad should not appear again in the form complained of. We told Beiersdorf UK Ltd t/a Eucerin not to state or imply that you could “look up to 5 years younger” with Eucerin Hyaluron-Filler Epigenetic Serum product, unless they held robust evidence to substantiate the claim.
