Section 3 of the Advertising Act · IT, Software & E-commerce

What an influencer may say about a product: health claims, medicines and comparisons with competitors

Influencer campaigns most often focus on labelling advertising, yet what the creator says about the product carries the same risk. For foods and food supplements there is a list of permitted health claims; for comparison with competitors, strict conditions under the Advertising Act. This article is for e-shops and brands that give creators a free hand.

A content creator receives a parcel of food supplements and says in a video that after a month her joints stopped hurting and that this is better than a well-known competing brand. Ideal for the reach of the post, but a legal problem in two places at once. Under the definitions in Act No. 147/2001 Coll. on advertising, a creator who publishes advertising is its disseminator, and the brand that ordered the dissemination from her is the party commissioning the advertising (Section 2(1)(c) and (f)). Both are therefore responsible for the content of the claims, each for a different part.

Foods and supplements must not appear to be medicines

The Advertising Act prohibits presenting foods and supplements as though they had medicinal effects:

Advertising must not […] present foods and food supplements as though they had the effects of medicinal products […]

— Section 3(1)(f) of Act No. 147/2001 Coll. (unofficial English translation)

The same prohibition follows from Regulation (EU) No 1169/2011 on the provision of food information. Food information must not attribute to any food the property of preventing, treating or curing a disease, and this rule expressly extends to advertising as well (Article 7(3) and (4)). The sentence “my joints stopped hurting” in a video about a food supplement creates the impression of a medicinal effect, even where the creator utters it as personal experience.

Health claims only from the list

Beyond medicinal effects there is room for health claims, but it is narrow. Under Regulation (EC) No 1924/2006, a claim is any message or representation, including pictorial representation, which states, suggests or implies that a food has particular characteristics (Article 2(2)(1)). For health claims:

Health claims shall be prohibited unless they comply with the general requirements in Chapter II and the specific requirements in this Chapter and are authorised in accordance with this Regulation and included in the lists of permitted claims provided for in Articles 13 and 14.

— Article 10(1) of Regulation (EC) No 1924/2006

The creator therefore cannot improvise. She may use only a claim authorised for the substance in question, in wording corresponding to the list. A health claim is moreover permitted only if the labelling of the product, or, where there is no such labelling, the presentation and advertising, contains the mandatory information, for example a statement on the importance of a varied and balanced diet and a healthy lifestyle (Article 10(2)). The same EU regulations apply in Czechia, and Czech advertising legislation additionally requires advertising for a food supplement to contain clearly legible text identifying it as a food supplement (Section 5d(3) of Act No. 40/1995 Sb.).

Comparison with competitors

Comparative advertising is advertising which directly or indirectly identifies another competitor or its products (Section 4(1)). It is permissible only on the conditions listed in the Act, among them that it compares products serving the same purpose, objectively compares material and verifiable characteristics, does not discredit the competitor, does not take unfair advantage of its reputation and is not misleading (Section 4(2)). Any other comparative advertising is impermissible (Section 4(3)). The burden of proof lies with the brand: in the proceedings, the party commissioning the advertising must, at the supervisory authority’s request, submit evidence of the accuracy of the factual data within 15 days, failing which the comparative advertising is deemed impermissible (Section 11(2)). A claim that something is “better than brand X” without measurements to support it is therefore primarily a risk for the party commissioning the advertising.

Who supervises and who pays

Supervision of advertising is divided according to the product. Advertising of foods is supervised by the official food control authorities, advertising of cosmetics and food supplements by the public health authorities, advertising of medicinal products by the State Institute for Drug Control, and other advertising by the Slovak Trade Inspection (Section 10(1)). For presenting foods and supplements as medicines, the supervisory authority may impose a fine on the disseminator of the advertising, and therefore on the creator too, ranging from EUR 300 to 4 % of turnover, up to a maximum of EUR 100,000. For impermissible comparative advertising, the party commissioning it faces a fine from EUR 1,000 to 6 % of turnover, up to a maximum of EUR 200,000 (Section 11(3)(c) and (e)). On finding an infringement, the supervisory authority will prohibit dissemination of the advertising and may also order publication of a corrective statement (Section 11(1)).

What belongs in the contract with the creator

The contract should contain a list of the claims the creator may use and an express prohibition of claims about treating and preventing disease. For foods and supplements, this means claims from the list of authorised claims in their precise wording; for comparisons, only data the brand can substantiate. To this should be added approval of the script and of the final post before publication, a duty to amend or withdraw a post at the brand’s request, and rules on who bears the consequences if the creator departs from the approved text. Labelling the collaboration as advertising is a separate obligation, discussed in labelling advertising by an influencer, and rights to the content created are covered in the article licence to influencer content.

We prepare a contract with the creator including content approval and a list of claims through our influencer contract service. Campaigns, competitions, reviews and an e-shop’s terms and conditions as a whole are covered by our legal services for e-shops.

This article provides general legal information as at 12 September 2026. It does not constitute legal services or advice on your specific matter. Laws change and the details of your situation may differ. Check the appropriate course of action or contact us before making a decision.

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Mgr. Patrik Tulinský, LL.M. Czech and Slovak attorney · SAK 300422 · ČAK 19654

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