Five of the global issues most frequently debated today are the decline of biodiversity in general and of agrobiodiversity in particular, climate change, hunger and malnutrition, poverty and water. The five issues are connected with each other, and as such, they should be dealt with. In this paper we show how seed is central to all five issues. Most of our food comes from seeds (even when we eat meat, we indirectly eat plants, which are coming from seeds) and food affects our health. Therefore, talking about seeds means talking about our health. The way in which seed is produced has been the cause and can be the solution to all five issues. The evolution of plant breeding, the science which is responsible for the type and the diversity of seed that farmers plant, and hence for the diversity of food that we eat, helps understanding how agrobiodiversity decreased. GMOs can only be a short term and unstable solution to food security because they change the environment surrounding the organisms they intend to control, so that, as predicted by the Fundamental Theorem of Natural Selection they evolve resistance. An agro ecological model of agriculture could be solution to the most important problems affecting the planet, but is often criticized for not being able to produce enough food for a growing population casting doubts on whether food security and food safety can be compatible objectives. Participatory and evolutionary plant breeding, while benefiting from advances in molecular genetics, reconcile increased production of more readily available and accessible food, with increased agrobiodiversity while maintaining the evolutionary potential of our crops needed to cope with climate change. Being based on selection for specific adaptation, participatory and evolutionary plant breeding are able to produce varieties specifically adapted to an agro ecological agricultural model which can reconcile food safety with food security.