The findings “show that cannabis was not safe for the long-term users tracked in our study,” University of California/Davis Associate Professor Magdalena Cerdá, the study’s lead researcher, said in a press release. “Alcohol is still a bigger problem than cannabis because alcohol use is more prevalent than cannabis use,” Cerda added. “But as the legalization of cannabis increases around the world, the economic and social burden posed by regular cannabis use could increase as well,” she said.
Researchers found that regular cannabis smokers “ended up in a lower social class than their parents, with lower-paying, less skilled and less prestigious jobs than those who were not regular cannabis smokers." "These regular and persistent users also experienced more financial, work-related and relationship difficulties, which worsened as the number of years of regular cannabis use progressed,” according to the press release. “Regular long-term users also had more antisocial behaviors at work, such as stealing money or lying to get a job, and experienced more relationship problems, such as intimate partner violence and controlling abuse.” “Our data indicate that persistent cannabis users constitute a burden on families, communities, and national social-welfare systems. Moreover, heavy cannabis use and dependence was not associated with fewer harmful economic and social problems than was alcohol dependence.”
The study, “Persistent Cannabis Dependence and Alcohol Dependence Represent Risks for Midlife Economic and Social Problems: A Longitudinal Cohort Study,” was published March 23 by the journal Clinical Psychological Science. It was co-authored by nine researchers from five universities, including four in the United States and one in England. The 947 study subjects were taken from a group of 1,037 members of the Dunedin Longitudinal Study, individuals born in Dunedin, New Zealand in 1972 to 1973, who have undergone assessments from the age of 5 to 38. Using the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, the study categorized their cannabis use from “never used” to “persistent dependence,” defined as use on four or more days per week.