There has been a common misconception about the relationship of cannabis to schizophrenia. For several years, some people believed the narrative that the more you consume the substance, the more likely you will develop mental health problems.
There have been a handful of tales supporting the claim that says that cannabis is not good for the brain especially among adolescents and that the heavy use could lead to a higher risk of acquiring a psychotic disorder.
A lot of research regarding the positive effects of cannabis have been published since then, some of them contradict the claim that the heavy use of the substance can lead to schizophrenia or any other psychotic disorder.
As a matter of fact, according to a recent research, the relationship may be the other way around – schizophrenia may lead to heavy cannabis consumption.
A study published by the Nature Neuroscience Journal stated that “Cannabis use is a heritable trait that has been associated with adverse mental health outcomes.” In other words, those who are genetically susceptible to schizophrenia are more likely to become heavy consumers of cannabis.
Researchers of the study were able to arrive at this conclusion through the examination of patients genetic coding. According to the researchers, it may be that consuming cannabis in the early stages of schizophrenia is a form of self-medication in an attempt to control or stop the recurring symptoms.
A team of scientists that are members of the International Cannabis Consortium and a number of known academic institutions worked hand in hand studying the anonymous genetic data of more than 180,000 test subjects. The Queensland Institute of Medical Research and Radboud University in the Netherlands are some of the key players of the research.
23andME, a personal biotechnology and genomics company provided some of the data that the study has used. Researchers also used the data gathered from a previous study that is kept by the UK Biobank.
Previous studies have often shown that schizophrenia and cannabis use are linked but they have also studied whether this association is causal, according to Jacqueline Vink who is the lead author of the research and a professor in the Behavioral Science Institute at Radboud University in the Netherlands,
She also added that their study showed that people with a vulnerability to develop schizophrenia have higher chances of using cannabis.
In their findings, a genetic overlap between those who are consumers of tobacco and alcohol and those who typically consume cannabis is notable.
This fact does not actually change anything because anyone who is familiar with cannabis consumers is aware that a lot of them are actually consumers of alcohol and cigarettes as well.
However, the author noticed a more significant overlap which is found between those who normally consumes cannabis and those who are genetically predisposed to schizophrenia.
The researchers concluded that individuals with those kinds of genes are predisposed to the use of cannabis.
One angle that they see as prevalent in most of the cases is that they use cannabis as a form of self-medication but they were quick to note that although this contradicts earlier research of the relationship of cannabis and schizophrenia, this does not dismiss the fact that cannabis can actually contribute to schizophrenia.
This is not the first study to make this type of claim. A study that was published in Molecular Psychology last 2014 say that genes signifying the likelihood of an individual to become schizophrenic increases the possibility of cannabis use. Clearly, the study by Vink coincides with the claim of this study from 2014.
However, even with the empirical evidence showing that in fact, schizophrenia can increase cannabis use, and not the other way around, it does not remove the possibility that a reverse cause and effect scenario will take place.
Which means that heavy consumption of marijuana could still contribute to one’s risk of slowly developing schizophrenia, like what the previous studies have stated.
Since then, the debate between the relationship between cannabis and psychotic disorders have been messy and until know, a clear line of thought is not yet concretely established.
However, with researches like Vink’s and her team, showing significant empirical results, it could be a step closer in establishing a clear correlation on how marijuana and psychotic disorders are linked with each other.