The current paper explores recent changes in food insecurity among adolescents and determine if food security concerns are associated with poorer wellbeing. Data were collected as part of two nationally representative surveys of the health and wellbeing of high-school students in New Zealand in 2007 and 2012. In 2012, 11% of young people reported food security concerns often or always, with 33% reporting food security concerns occasionally/sometimes. The prevalence of food security concerns at both frequencies increased significantly from 2007 (8% and 28%, respectively). Young people with food security concerns were more likely to report poor indicators of health and wellbeing, including truancy, poor general health, mental health concerns and obesity. Our findings highlight the growing concerns of food insecurity reported by adolescents in New Zealand. Interventions that address food security for families may provide a tangible means of promoting the healthy development of children and young people.