Alcohol and cannabis are often associated with adverse effects on the human brain. However, a recent study reveals that marijuana does not cause any harm to the brain structure. In contrast, the chronic use of alcohol has an adverse impact on gray matter volume and white matter integrity.
A study conducted by American researchers became available online before its publication in the journal Addiction. According to the data, cannabis consumption has no links with brain changes, unlike alcohol use, which negatively affects the brain structure.
Researchers from the Oregon Health & Science University and the University of Colorado Boulder investigated the impact of alcohol and marijuana use on structural neuroimaging in teenagers and adults. During the study, the scientists analyzed the brain activity of 853 adults and 439 teenagers who consumed either marijuana or alcohol in the past 30-day period.
The main goal of the study was to reveal any association between alcohol or marijuana use and changes in gray matter volume or white matter integrity. The findings showed a negative correlation between alcohol use and brain structure, while no connection with the use of marijuana was found.
According to the study, the chronic use of alcohol reduces the gray matter volume in adults and teenagers, as well as lowers white matter integrity in adult samples. In contrast, the researchers observed no changes in the brain structure of marijuana users.
The results of the research are similar to those shown in previous studies on the matter. The scientists believe that the popular assumption that marijuana negatively affects the human brain was based on the fact that the investigated cannabis users also consumed alcohol.
A 2015 study that analyzed the brain morphometric measures in daily cannabis users found no association between marijuana use and long-term negative changes in the brain morphology. At the same time, the use of alcohol was found to have a negative influence on cognition and brain.
In addition, earlier this year, the British Medical Journal published a study that showed that even moderate use of alcohol resulted in adverse effects on the brain, such as hippocampal atrophy.