New research [...] finds that reported exposure by youth to tobacco marketing was associated with co-use of tobacco and cannabis on a given day. To reach this result, researchers examined daily locations of youth, their travel patterns, and their exposure to tobacco retail marketing to learn about how these factors contribute to youth tobacco and cannabis use and co-use. [...] Dr. Sharon Lipperman-Kreda says that "this study highlights the importance of policies and interventions addressing young people's exposure to and perception of exposure to tobacco marketing at the point of sale in the broader environment to reduce tobacco and cannabis use and co-use."