New Study Challenges Cannabis Myths About Brain Health and IQ

Groundbreaking Study Challenges Long-Held Beliefs About Cannabis and Cognition

A new study spanning 44 years and involving over 5,000 men has challenged widely-held views on cannabis use and its impact on cognitive decline. The research suggests that cannabis users experienced slightly less cognitive decline than nonusers over a long period.

Key Findings

Cognitive Decline: Cannabis users experienced a 1.3 IQ point advantage in maintaining cognitive function over 44 years compared to nonusers.

Initiation Age: Starting cannabis use before the age of 18 showed no significant impact on long-term cognitive decline.

Frequency of Use: Regular use (≥2 times per week) did not correlate with greater cognitive decline.

A Nuanced Look at Cannabis and Brain Health

Cannabis has often been maligned for its short-term cognitive effects, with many assuming long-term damage to mental sharpness. However, this study, conducted in Denmark, sheds light on a more complex relationship between cannabis and cognition.

The study followed men from early adulthood into their late midlife, measuring cognitive changes with intelligence tests. Interestingly, cannabis users showed a modest advantage in preserving IQ scores over the decades, even after adjusting for lifestyle factors such as education and other substance use.

Challenging Assumptions

Historically, research has suggested that cannabis contributes to cognitive decline, particularly with long-term use. However, this study disputes that assumption, suggesting that other factors—such as baseline IQ, educational level, and lifestyle—may have a greater influence on cognitive aging than previously thought.

The differences in cognitive decline between cannabis users and nonusers were modest, and while statistically significant, they may lack clinical relevance. Nonetheless, the findings open the door for future studies to explore the long-term effects of cannabis on cognition in more detail.

Funding and Support

The study was supported by various grants, including those from Innovation Fund Denmark, Health and Clinical Research, the University of Copenhagen, and other institutions. The funding bodies had no involvement in the study’s design or data analysis.

As the debate around cannabis and its cognitive effects continues, this research offers a refreshing perspective, suggesting that the relationship between cannabis and cognitive health may be more intricate than previously believed.