Throughout the years, there has been a controversy regarding the topic of smoking marijuana and whether it’s good or bad for you. I have encountered people that say smoking marijuana doesn’t harm your body, and other people that say it’s absolutely terrible for you. With the legalization of marijuana in various places around the world, including in some states in the U.S. such as Colorado, I decided to research both sides of the argument and see if there are health risks involved with smoking marijuana.

The International Lung Cancer Consortium conducted a study to investigate the correlation between cannabis smoking and lung cancer risk. They collected data on 2,985 people from 6 case-control studies in the U.S., Canada, UK, and New Zealand. Several variables were considered in this study, such as sociodemographic factors and tobacco-smoking status. They were divided into groups according to amount of marijuana smoked, such as habitual smokers, nonhabitual smokers, and people that had never smoked. Habitual individuals were categorized that way if they smoked a joint or more per day for 10 years. The researchers studied the number of people who got lung cancer, and found that there is a weak association between smoking marijuana and getting lung cancer, with non-tobacco smokers. However, since this correlation was so low, the study concluded that there is little evidence for an increased risk of getting lung cancer either for habitual or nonhabitual cannabis smokers.

While studies might suggest that there is little correlation between lung cancer risk and smoking marijuana, there are other studies that argue that marijuana use has an adverse effect on brain development. A study conducted by the Oxford University Press researched if there is a correlation between cannabis use and working memory and neuroanatomical differences. The study was conducted by comparing brains of people with cannabis use disorder and brains of people with schizophrenia. “The subject groups had matching demographics, and they included 44 healthy controls: 28 with schizophrenia with no history of substance abuse, 10 with cannabis use disorder, and 15 with schizophrenia and cannabis use disorder.” The researchers obtained representations of the thalamus, globus pallidus, and striatum, using an HD mapping with MRI system. There were significant cannabis-related differences across both cannabis use disorder groups, particularly in the striatum, globus pallidus, and thalamus. The schizophrenic/cannabis use disorder group showed greater neuroanatomical differences compared to the other cannabis-use group. These results show that both cannabis-use groups had working memory deficits as well as neuroanatomical differences. However, the study was not entirely clear in explaining the results of the experiment. The study hasn’t been able to determine if the use of cannabis contributes to the differences in shape, or if these differences in shape are caused specifically by smoking marijuana.

My final takeaway on this topic is that clearly smoking marijuana has some adverse side effects on the brain, as seen in the Oxford University Press study. However, according to the first study mentioned, there is little to no correlation between smoking marijuana and lung cancer. I only researched the effects of marijuana on the brain and lungs though, so it’s possible that marijuana affects other parts of the body either adversely or with no consequence.