The article shows the results of research that aimed to foster the development of the argumentative skill in a group of teachers in initial training of the National Pedaggical University’s Chemical Licensing Programme, by designing and implementing a lesson on the implications of food chemistry on the development and prevention of Parkinson’s disease [EP] as a sociocidal issue. Activities were implemented such as open questions, discussion forums and the search for possible nutritional alternatives in the prevention and treatment of the EP. At each stage, the level of argumentation was identified and the conceptual content of each argument was analysed. It is highlighted that students managed to reach a higher level of argumentation than initial by applying the knowledge acquired in resolution and finding alternatives through active and reflective learning. They built arguments based on theoretical and experimental bases on different aspects of this dispute.