Mackenzie Betteridge is a doctoral student in Health and Rehabilitation Sciences under the Health Promotion stream at Western University. She is co-supervised by Dr. Jamie Seabrook and Dr. Jason Gilliland. Her graduate work to date has explored sociodemographic, psychological, health-behaviour, and neighbourhood-level factors that shape cannabis use among adolescents across Canada. She is passionate about understanding how young people’s environments, lived experiences, and lifestyle behaviours influence their substance use. Looking ahead, she hopes to expand this work by examining patterns of polysubstance use among youth, with the goal of supporting more comprehensive and responsive public-health approaches. Within the HEAL, Mackenzie is part of the QuaranTEENing project and a staff co-facilitator for the youth advisory council (HEALYAC).