King’s College London, which is ranked one of the top 10 universities in the U.K., recently announced that it would be launching a study to examine the effects of cannabis on mental health.

Marta di Forti (MRC Senior Clinical Fellow) will lead the study. Marta has previously conducted cannabis-based research. “We wish to reach out to those out there using cannabis, in particular those benefiting from it. Without their help we will continue to have a polarised debate on cannabis, with us thinking it is all bad and should be banned, and others believing that because it is a plant it cannot have adverse effects,” di Forti said.

The study, called “Cannabis & Me (CAMe)”, is fully funded by King’s College London. It was submitted by Di Forti to the MRC initially in 2019. The MRC approved it in 2020, with a $2.5million grant. “The pandemic has delayed the start to this date. There are many labs involved in the study, all of which have been affected by COVID-19. Finally, everyone is ready to start,” di Forti explained. It will run for five-years, with the first results expected to be available in early 2023.

In a description of the study’s purpose, authors explained the need for more research in light of the rapid increase of consumers across the globe.  “Therefore, at a time when cannabis use is increasing worldwide, this study focuses on understanding the wider impact of cannabis use on the physical and mental health of cannabis users. It also aims to identify environmental and biological factors, which can explain the different effects people experience when using cannabis, and in particular, identify those users more likely to experience mental health and social issues.”

There will be 6,000 participants, aged 18 to 45. Participants must live in London. They will be required not only to take part in an online study, but must also agree to a face-to-face assessment, blood sample donation, and a VR experience (which will be used to measure an individual’s physiological response to specific situations). Participants who are not currently being treated for psychotic disorders should be aware that they will need to have an online assessment.

Participants will be chosen for in-person interviews based on current cannabis consumption, or having “never/only twice” tried cannabis.

“The main aim of the study is to understand why a minority of cannabis users experience psychological and cognitive adverse effects—this is the clinical population I care for as a clinician,” di Forti said. “If we can identify the environmental and biological factors that make a minority susceptible to adverse effects when using cannabis daily either for medicinal or recreational reasons, we can inform safe prescribing and side-effects monitoring (we use virtual reality to test if or how cannabis affects reality perception).”

Di Forti said that there is a need to provide more information on possible side effects and benefits of cannabis. “We can also offer more information to the general public, to avoid adverse effects when using cannabis and how to recognise them,” she said. “Everyone in our society can recognise the negative effects of excessive alcohol consumption, but not everyone is familiar on how to identify the changes in thinking, processing and cognition that a minority experience when using cannabis.”

Studies have been done in the past by di Forti to examine the relationship between cannabis and psychotic disorders. In the results from a 2015 study, she came to the conclusion that “risk of individuals having a psychotic disorder showed a roughly three-times increase in users of skunk-like cannabis compared with those who never used cannabis.” The results of this study have been used to support anti-cannabis efforts, which di Forti does not approve of. “Sometimes the political debate about cannabis has used my data in a context which doesn’t necessarily represent my view, and this is what tends to upset me,” di Forti said in an interview with Cannabis Health. “People now associate me with the idea that nobody should use cannabis and that cannabis is a toxic substance, which is not what I think.”

Another recent study associated with King’s College London found evidence that teen and adult smokers are not less likely to be motivated because of their cannabis use. COVID-19 sufferers also had less severe symptoms when cannabis was used.