Background: Exposure to marketing for foods high in sugar, salt, and fat is considered a key risk factor for childhood obesity. To support efforts to limit such marketing, the World Health Organization Regional Office for Europe has developed a nutrient profile model (WHO NPM). Germany's Federal Ministry of Food and Agriculture plans to use this model in proposed new legislation on food marketing directed towards children, but the model has not yet been tested on products on the German market. Against this backdrop, the present paper aims to assess the feasibility and implications of implementing the WHO NPM in Germany. Methods: We applied the WHO NPM to a random sample of 660 food and beverage products across 22 product categories on the German market drawn from Open Food Facts, a publicly available product database. We calculated the share of products permitted for marketing to children based on the WHO NPM's nutrient and ingredient criteria, both under current market conditions and for several hypothetical reformulation scenarios. We also assessed effects of adaptations to and practical challenges in applying the WHO NPM. Results: The median share of products permitted for marketing to children across the model's 22 product categories was 20% (interquartile range (IQR) 3-59%) and increased to 38% (IQR 11-73%) with model adaptations for fruit juice and milk proposed by Germany's Federal Ministry of Food and Agriculture. With targeted reformulation (assuming a 30% reduction in fat, sugar, sodium and/or energy) the share of products permitted for marketing to children increased substantially (defined as a relative increase by at least 50%) in several product categories (including bread, processed meat, yogurt and cream, ready-made and convenience foods, and savoury plant-based foods), but changed less in the remaining categories. Practical challenges in applying the model included the ascertainment of the trans-fatty acid content of products, and the classification of products not required to carry nutrient declarations, such as fresh meats, fish, and similar products. Discussion: The application of the WHO NPM to a random sample of food and beverage products on the German market was found to be feasible. Its use in the proposed new legislation on food marketing in Germany seems likely to serve its intended public health objective of limiting marketing in a targeted manner specifically for less healthy products. It seems plausible that it may incentivise reformulation in some product categories. Practical challenges in applying the model could be addressed with appropriate adaptations and procedural provisions.

PvP reports receiving research funding from Germany's Federal Ministries of Food and Agriculture (BMEL), Education and Research (BMBF) and the Environment and Consumer Protection (BMUV), as well as travel costs and speaker and manuscript fees from the German and Austrian Nutrition Societies (DGE and OEGE), the German Diabetes Society (DDG) and the German Obesity Society (DAG). OH is an employee of the German Diabetes Society (DDG) and the German Obesity Society (DAG), and has previously been an employee of foodwatch. CK reports being a member of the German Nutrition Society (DGE) and the BerufsVerband Oecotrophologie e.V. (VDOE). ER reports receiving research funding from Germany's Federal Ministries of Food and Agriculture (BMEL) and Education and Research (BMBF). The staff positions of NH, AL, CK, EO, KG and PvP are partly or fully funded through research grants from Germany's Federal Ministries of Food and Agriculture (BMEL) and Education and Research (BMBF). The other authors state that they have no conflicts of interest to declare.

https://osf.io/bjevc

This work was conducted without external funding through staff positions at Ludwig-Maximilians-Universitaet Muenchen (LMU Munich), Germany, and the German Obesity Society (DAG), Berlin, Germany.

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