This report was commissioned by the German Food Association (Lebensmittelverband Deutschland e.V.) from Katharina Schüller, CEO STAT-UP GmbH and member of the board of the German Statistical Society, and Prof. Walter Krämer, Prof. em. TU Dortmund. In their work, they analyse the scientific and statistical basis of a widely demanded advertising ban on foods that do not meet the requirements of the WHO nutritional profile model for Europe (WHO, 2023) in terms of their sugar, salt or fat content.
According to the authors, there is no evidence of a direct, causal link between children's exposure to advertising and increased overweight or even obesity. There is no clear scientific evidence of the lasting effect of advertising on the increased consumption of so-called HFSS foods (high in fat, salt or sugar) in children, nor does any study establish a causal link to obesity. On the contrary, this connection has hardly been investigated at all. Current research is only focussing on the very limited consumption (often less than one hour) of HFSS foods by children following their exposure to HFSS food advertising.
A scientific basis from which an evidence-based ban on health promotion advertising could be derived is therefore not sufficiently given. On the contrary, all the studies analysed and cited in the context of the ban under discussion
either do not make any such claims,
are not methodologically constructed in a suitable way to show a causal relationship to health endpoints (overweight, obesity), or
are so flawed in terms of content and methodology that the study's conclusions are unfounded.
The first point of criticism relates to the fact that study results are misinterpreted by third parties. For example, Prof Bertold Koletzko, Chairman of the Children's Health Foundation, falsely claims that the study situation on the influence of advertising on children's nutrition is "crystal clear" (Roggenkamp, 2023).
The second point of criticism includes the problem that possible risk factors, which are actually responsible for the occurrence of the observed effect, are not taken into account or that the observation period is simply too short.
The third point of criticism, methodological shortcomings, can be seen in the form of so-called "alpha error inflation" (Type I error inflation), a lack of discussion of methodological weaknesses and statistical uncertainty as well as unsuitable statistical methods.
In addition to these points of criticism, the authors of the report identify the problem of publication bias. This occurs when studies with statistically significant effects are published more frequently in scientific journals, resulting in above-average publication of random effects.
At the end of the report, the authors briefly outline how a scientifically sound study to investigate the advertising effects of HFSS products on children's health would have to be structured in order to provide a statistically and methodologically sound evidence base.
References
Roggenkamp, G. (2023). Kinderschutz hat Priorität: Werbung für Dickmacher jetzt stoppen! Pressemitteilung der Stiftung Kindergesundheit. http://idw-online.de/de/news809923
WHO. (2023). WHO Regional Office for Europe nutrient profile model: Second edition. WHO Regional Office for Europe. https://www.who.int/europe/publications/i/item/WHO-EURO-2023-6894-46660-68492
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