Cannabis: How does it affect your health? What’s safe and what isn’t?

  • Nature's Source

With the legalization of cannabis in Canada, it is important to familiarize yourself what is and is not safe use of the drug.

When talking about cannabis, we can simplify our discussion and break it down into two main components of the plant; delta-9-tetrahydrocannibinol (THC) and cannabidiol (CBD). These two constituents of cannabis have differing effects and are being studied extensively in human populations.

THC is intoxicating and can affect your motor functions, impair your memory, and potentially cause heightened anxiety and/or depression. In those with a family history of schizophrenia, cannabis use may trigger a psychotic episode, causing the user to have difficulty distinguishing reality from hallucinations.

If someone chooses to smoke cannabis long-term, the damage can hurt their lungs and make it more difficult to breathe.

Though people often associate lung problems with tobacco products, smoking cannabis will cause oxidative damage to the lungs since many of the same harmful chemicals in tobacco smoke are still produced.

Long-term use of cannabis may also worsen anxiety and depression, as well as potentiate the risk of developing an addiction to the plant. It appears that using cannabis or cannabis products with high levels of THC may further increase the risk of developing mental health problems in the long-term.

Cannabinoid hyperemesis syndrome is a condition that causes cyclical nausea & vomiting, and frequent hot bathing (1). If you suffer from these symptoms and are a regular cannabis user it is important to speak with your doctor.

So what about the potential health benefits attributed to cannabis use?

It is important to note that while the following studies utilized cannabis extracts, they are not yet legal in Canada. The same goes for topicals and edibles, though the government has clarified that they will be legal later this year.

There are conflicting reports of whether cannabis smoking harms male fertility. While studies looking at human and animal cannabis abuse confirm adverse effects to sperm health, data on moderate consumption is scarce. A recent study using Male fertility patients looked at subfertile men who had ever smoked cannabis. The results indicated that both past and present smokers of marijuana actually had higher levels of sperm concentrations compared to men who had never smoked (5). More research on marijuana use and fertility is still needed.

A team of researchers in Australia looked at the use of cannabis in treatment-resistant forms of childhood epilepsy (2). Researchers found that parents treating their kids with medical cannabis extracts saw a large reduction in their symptoms; up to 75%. CBD was long thought to be the main constituent of cannabis that provides a therapeutic benefit. However, the researchers noted that the parents were using products with low levels of CBD content, and that THC and THCA were slightly more responsible for the anticonvulsant effects. An important takeaway from the study is that cannabis constituents work synergistically, so it is important to consider the plant as a whole in future treatment research.

Researchers in South London looked at the potential of CBD to be a therapeutic intervention for clinically high risk female psychosis patients. The study used a single oral dose of 600 mg of CBD for 16 participants in the treatment group and placebo for 17 controls. Both groups were deemed clinically high risk. The CBD group was found to have significantly more brain normalization in areas associated with a high risk of psychosis (3). Though more research is needed, CBD extract may be a helpful approach for psychotic symptoms.

As with any new therapy, speaking to your doctor, pharmacist, and specialists will help to clarify if cannabis use is right for you. Furthermore, visiting the government of Canada’s website will help you learn the legalities and health effects associated with cannabis.

1. Galli JA., et al. Cannabinoid hyperemesis syndrome. Curr Drug Abuse Rev 2011; 4(4): 241-249.

2. Suraev A. Lintzeris N, Stuart J, et al. Composition and Use of Cannabis Extracts for Childhood Epilepsy in the Australian Community. Scientific Reports volume 8, Article number: 10154 (2018).

3. Bhattacharyya S, Wilson R, Appiah-Kusi E, et al. Effect of Cannabidiol on Medial Temporal, Midbrain, and Striatal Dysfunction in People at Clinical High
Risk of Psychosis: A Randomized Clinical Trial. JAMA Psychiatry. 2018;75(11):1107–1117. doi:10.1001/jamapsychiatry.2018.2309

4. html accessed July 30, 2019; last updated June 14, 2019.

5. Feiby L Nassan, Mariel Arvizu, Lidia Mínguez-Alarcón, Paige L Williams, Jill Attaman, John Petrozza, Russ Hauser, Jorge Chavarro, Marijuana smoking and markers of testicular function among men from a fertility centre, Human Reproduction, Volume 34, Issue 4, April 2019, Pages 715–723,