Latrines and cesspits have been the most useful architectural resource used in societies without sewage facilities. In these cavities drilled in the ground, at a certain distance from the water table to avoid contamination, urban populations have deposited both organic and inorganic remains resulting from their daily activities. These small dumps have become very important points of information for archaeologists to learn about the practices and diets of past societies. In the present study, we have collated archaeobotanical materials identified in different latrines and cesspools from medieval contexts in the Iberian Peninsula (Catalonia, Andalusia, Extremadura), within the research framework of the MEDGREENREV REF. 101071726 funded by the Europe Research Council within the Synergy Grants programme. By focusing on the on hundreds of thousands of archaeobotanical remains, we can discern the discards of culinary and food processes within medieval urban societies. These results make it possible to draw up a list of the main consumed plants, but also to detect the presence of rare introduced taxa, potentially due to the privileged status of the sites' inhabitants. Each case study is unique, as each population has different agricultural, trading and gathering capacities, and this summary will highlight the similarities and differences between the sites and regions.