Marijuana seems to be growing in popularity and acceptance. However, we are still learning about its effect on the developing brain. As new information comes out, I would like to share it with you, allowing you to continue making wise decisions for you and your children. With that in mind, I want to share the outcomes of two studies published this year (2024).

The first, a study published in Nature Mental Health utilized data from the Adolescent Brain and Cognitive Development (ABCD) Study, which is an ongoing research project in the United States that includes “nearly 12,000 children.” In this study, researchers collect data about the mothers’ substance use prior to birth as well as neuroimaging data of their children at 9-to 10-years-old and 11-to 12-years-old. Around 370 children were exposed to cannabis prior to the mother learning she was pregnant and 195 were exposed to marijuana both prior to and after the mother learned she was pregnant. The neuroimaging of the children revealed that those who experienced prenatal exposure to cannabis exhibited changes in brain structure and inflammation. These changes in brain structure and inflammation were associated with mental health conditions in childhood and adolescence.

A second study, published in the Journal of Neuroscience, revealed that adolescents who use cannabis were more likely to have a thinner cerebral cortex. This appeared to result from a “shrinkage of the dendritic arborization, in a sense the connecting branches between neurons and essential for the communication between neurons. This decreased connection makes it more difficult for the brain to learn new things, interact, cope with new situations, etc.” “In other words, it makes the brain more vulnerable to everything that can happen in a young person’s life.” It interferes with learning and growing.

Taken together, these two studies suggest that marijuana use can hinder the healthy development of our children’s brains and our adolescents’ brains are especially vulnerable to the negative effects of marijuana. In addition, this impact can begin with prenatal exposure to marijuana. Although marijuana is increasingly proclaimed as safe, it may not be safe for our children or our teens and their developing brains. In fact, it may hinder the healthy development of their brains.