The legalization of marijuana has been a popular topic since it was initially outlawed in the 1970s. The past several decades have seen a significant shift in public perception, with many addressing the drug as a more peaceful alternative to alcohol or the ‘harder’ substances. Two states in America have legalized cannabis, and now with Justin Trudeau promising to work towards doing the same in Canada, it seems like the days of prohibition and ‘reefer madness’ are far behind us.
There’s only one problem: while we were working towards legalization,many of those who grew the plant for medicinal use or otherwise have tinkered with the potency so much that it is simply not the same drug people were enjoying 50 years ago. Marijuana’s main psychoactive ingredient, tetrahydrocannabinol (THC), is incredibly more concentrated in the majority of modern day weed, reaching an average of 14 percent compared to the 4 percent found in older strains.
This doesn’t just mean that cannabis will generally get you higher; it also means some of the older research conducted with the drug has become more or less irrelevant. Now, researchers are beginning to find connections with mental illnesses like schizophrenia and psychosis, and they are becoming increasingly more difficult to ignore as the drug’s potency continues to rise.
In a recent study done by researchers at Kings College London, the brains of marijuana users were found to have smaller amounts of white brain matter inside their corpus callosum, a neural pathway that connects the left and right halves of the brain, than those who don’t partake. White matter essentially regulates the nerve signals sent between different areas in the brain, meaning that damaging it can cause significant communication problems within the central nervous system. Not only did the pot smokers show more damage than non-smokers, but those who smoked stronger types of cannabis (which the study refers to as ‘skunk’) also showed the most white matter loss.
MRI scans were performed on the brains of 56 patients who had visited a London hospital to report a first episode of psychosis. The brains of 43 healthy participants were then scanned as well, and each individual involved in the study was interviewed about their drug habits.
“We found that frequent use of high-potency cannabis significantly affects the structure of white matter fibres in the brain, whether you have psychosis or not,” said neurobiologist at Kings College, Paola Dazzan, in a press release. “This reflects a sliding scale where the more cannabis you smoke and the higher the potency, the worse the damage will be.”
There have been similar findings in the past, with the most recent study – published in the scientific journal Psychological Medicine last week – proving that further research needs to be done before we can determine what constitutes safe use.
“As we have suggested previously, when assessing cannabis use it is extremely important to gather information on how often and what type of cannabis is being used,” explained Dazzan. “These details can help quantify the risk of mental health problems and increase awareness on the type of damage these substances can do to the brain.”
“There is an urgent need to educate health professionals, the public and policymakers about the risks involved with cannabis use.” he added.
Of course, this doesn’t necessarily mean that smoking cannabis directly causes psychosis. In fact, many have criticized the likes of this study, saying that you can’t be sure that those predisposed to the condition aren’t instead more likely to become daily smokers. Still though, studies such as this help get a second opinion on the otherwise relaxed perception of marijuana’s long term effects. Even if there’s a slight chance that the drug can develop these mental illnesses, we need to take steps to ensure that the proper education is put out about its use – especially for teenagers with their still developing brains.
It’s important to note that while 14 percent is the general average, many other strains go far beyond that concentration, with some going up to 30 or even 40 percent. Fortunately cannabinol, marijuana’s weaker and more medicinal psychoactive chemical, has not yet been observed to have the same effects on the brain, but is it typically not as prominent in weed strains on the market. Perhaps the solution is to find a healthy balance between the the two ingredients that can maintain a similar potency without risking neural damage.