In two experiments, we analyzed cross-cultural differences in understanding and recalling information about medical risks in two countries—Germany and Spain—whose students differ substantially in their quantitative literacy according to the 2003 Programme for International Student Assessment (PISA; OECD, 2003, 2010). We further investigated whether risk understanding can be enhanced by using visual aids (Experiment 1), and whether different ways of describing risks affect recall (Experiment 2). Results showed that Spanish students are more vulnerable to misunderstanding and forgetting the risk information than their German counterparts. Spanish students, however, benefit more than German students from representing the risk information using ecologically rational formats—which exploit the way information is represented in the human mind. We concluded that our results can have important implications for clinical practice.