We might tend to think that cannabis burns our neurons. However, a study published in the Journal of Studies on Alcohol and Drugs and relayed by IFL Science provides a more nuanced point of view on THC consumption. Instead of a clear decline, researchers observed, in some cases, a slowdown in brain aging.
Scientists analyzed data from more than 25,000 people aged 40 to 77. The results are surprising: in individuals who have used cannabis moderately over the course of their lives, certain regions of the brain appear to have better resisted the passage of time. How can we explain this astonishing effect and how does it manifest in practice?
The study finds that certain areas of the brain crucial for memory and emotions, such as the hippocampus and amygdala, have greater volume in people who have used cannabis in the past. In general, these regions shrink with age, but here the phenomenon seems less marked.
In a group of more than 16,000 people who took cognitive tests, moderate consumers performed better in learning, speed of thinking and short-term memory. According to the study’s author, Anika Guha, all significant measures pointed towards better performance from consumers. Results which therefore go against many prejudices, but also serious studies on the subject, painting a less Manichean picture.
The role of brain receptors
Researchers believe that these effects could be linked to cannabinoid type 1 (CB1) receptors, which are present in large numbers in protected areas of the brain. These receptors interact with THC, the main active molecule in cannabis.
The hypothesis is that activation of these receptors could reduce inflammation in the brain and strengthen the natural defenses of this organ. This would help slow down the wear and tear of neurons. Surprisingly, these positive effects were observed even in people who had not used cannabis for decades, suggesting possible long-lasting protection.
However, researchers urge caution. The study shows an important difference by age: while cannabis appears to be associated with better brain health in older adults, it remains dangerous for adolescent brains, which are still developing.
Other limitations of this study: the effects could vary between men and women, and researchers have not yet clearly distinguished the difference in impact between THC and CBD. Scientists are therefore talking here about a correlation, a very present link but not sufficient to state with certainty that cannabis is the direct cause of this protection.
