Animal-free strategies in food safety & nutrition: What are we waiting for? Part II: Nutrition research

Background: Methods and approaches that can be used in food and nutrition research are changing at a faster pace than ever. Whereas animal methods are mostly known for their use in food safety analysis (see Part I), they also play in important role in proof-of-concept and mechanistic studies of products, as well as studying potency, efficacy, and tolerance of foods and food ingredients. Members of the International Life Sciences Institute (ILSI) Europe have formed an expert group to review possibilities, opportunities, and challenges for the potential use of alternative testing strategies in nutrition research and regulatory requirements, supporting the 3Rs principle of Replacement, Reduction, Refinement of animal research, which can ultimately be used in support of regulatory submissions for pre-market authorisation. Scope and approach: For the different areas of food for specific groups and health claims, the acceptability of nonanimal approaches is evaluated in comparison to legislative requirements in Europe. The alternative approaches considered cover emerging tools and methodologies such as organoids, organs-on-a-chip or human in vitro gastrointestinal simulators. Conclusions: In nutrition research, there has been a long tradition of following a certain experimental trajectory for grounding scientific hypotheses starting from in vitro data moving on to in vivo verification in a preferred animal model and finally proving this in a human setting. From a regulatory perspective there is no specific requirement for animal experimentation that justifies the use of the majority of animal experiments in the assessment of nutritional content and value of food products. However, animal data are mostly considered as the standard, and guidance for alternative approaches that would be accepted is lacking. It is therefore important to further build evidence and offer validation for the adequacy of already existing in vitro tools to ensure their suitability for substantiating dose levels and further planning clinical trials. What are we waiting for?