An analysis of data from the Victorian Adolescent Health Cohort Study that followed a sample of almost 2,000 Victorian school children from the age of 14 until the age of 35 found that social disadvantage, anxiety, and licit and illicit substance use (particularly cannabis), were all more common in participants who had reported self-harm during adolescence. People who self-harmed as teenagers were more than twice as likely to be weekly cannabis users at age 35. Anxiety, drug use, and social disadvantage were more common at age 35 among participants who had self-harmed during their teenage years. While most of these associations can be explained by things like mental health problems during adolescence and substance use during adolescence, adolescent self-harm was strongly and independently associated with using cannabis on a weekly basis at age 35. The authors concluded that adolescent self-harm is a conspicuous marker of emotional and behavioural problems that are associated with poor life outcomes.