A study spanning 44 years and involving over 5,000 men challenges long-held beliefs about cannabis and cognition. Researchers found that cannabis users experienced slightly less cognitive decline from early adulthood to late midlife compared to nonusers.
Neither the age of cannabis initiation nor the frequency of use showed a significant impact on cognitive decline. These findings suggest that long-term cannabis use might not impair—and could even modestly benefit—cognitive aging, although further research is needed to confirm the results.
Cannabis users showed a modest advantage in maintaining IQ levels over time, even when controlling for lifestyle factors such as education and substance use. Moreover, neither the age at which cannabis use began nor frequent use significantly accelerated cognitive decline. These findings challenge previous assumptions that cannabis usage contributes to steeper cognitive decline.
