Tag: cannabis use

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Neurologists Pin Down How Cannabis Causes Anxiety

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For the first time, Northwestern scientists have identified a set of neurons that play a role in generating anxiety after exposure to cannabinoid drugs, especially under stressful conditions. Cannabinoids are a class of substances that includes THC, the main psychoactive ingredient in cannabis.

In the study, the scientists exposed mice to a threatening odor. Before being exposed to the scent, derived from fox urine, the mice either received a placebo or a synthetic cannabinoid drug.

When they received the drug, the mice froze more often and spent less time investigating the predator door. These anxious behaviours, the scientists found, were linked to the drug’s activation of a small group of cells — known as somatostatin neurons — in the brain’s central amygdala, a region that processes fear and stress.

Importantly, when the scientists genetically silenced these somatostatin neurons, the drugged mice did not avoid the predator scent as much anymore.

“The results of this study could explain why a good trip can turn bad pretty quickly if people consume too much cannabis or the situation they are in turns stressful or scary,” said study senior author Dr Sachin Patel, chair of psychiatry and behavioral sciences at Northwestern University Feinberg School of Medicine.  

The study appears in Nature Communications.

How the study was conducted

Patel and colleagues tested several doses of the synthetic cannabinoid on mice and tracked how much time they spent near the predator odor, and whether they froze or fled from the scent. To simultaneously record brain activity, the team implanted a small microscope into the mice’s brain.

The scientists also conducted brain tissue experiments to analyse how the cannabinoids affected interactions between neurons. They found that the drug weakened the brain’s natural “brake” on the somatostatin neurons, allowing them to become more active.

“Higher doses of cannabinoids and environmental stress worked together to synergistically release the ‘brake’ on the central amygdala, which in turn drove excessive anxiety,” Patel explained.

Why the findings matter

Cannabis use in the US has steadily increased in recent years and so have emergency department visits related to adverse effects from the drug. Previous studies have also found an association between cannabis use and increased risk of anxiety in the long term. What’s more, anxiety and mood disorders are also on the rise globally.

“Understanding how cannabis affects brain function to generate its psychoactive effects could ultimately reveal new ways to counteract negative consequences should they arise in some people,” Patel said. 

Patel also noted that the findings could have implications beyond cannabis. “Suppressing the activity of somatostatin neurons in the central amygdala could represent a final pathway for reducing anxiety symptoms, not just in the context of cannabis side effects,” he explained.

Source: Northwestern University via EurakAlert!

Categories : Mental Health Substance UseTags :

More Frequent Cannabis Use Linked to Poorer Mental Health

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Research coauthored by a University of Miami Business School professor links more frequent cannabis use to fewer days of good mental health, particularly among men.

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More frequent cannabis use is associated with fewer days of good mental health among adults, particularly men, according to a study coauthored by a University of Miami Business School professor.

Michael T. French, professor and chair of the Department of Health Management and Policy, and Weiwei Chen, an economist at Kennesaw State University, examined how cannabis use relates to self-reported overall, physical and mental health. Their study was published in Medical Care Research and Review.

“People have some preconceived notions about alcohol and other drug use, including how they affect individuals, society and governments,” said French. “I believe this paper is another example of how our preconceived notions aren’t always correct, especially when it comes to cannabis use and related policies.”

The study examined the relationship between cannabis use and overall physical and mental health, added French, who has spent much of his career studying substance use policies and risky behaviours.

Cannabis use has become more prevalent as additional states pass medical and recreational cannabis laws. In April, FDA-approved cannabis medications and cannabis sold under state medical licences were moved out of the Schedule I classification they shared with heroin and into Schedule III, a category for drugs with accepted medical uses and a moderate risk of dependence, such as ketamine and Tylenol with codeine.

French and Chen applied statistical techniques to data on cannabis use, health status and other individual characteristics from the 2016–2023 Behavioral Risk Factor Surveillance System. The analysis included adults from 38 states and found that more days of cannabis use were associated with fewer days of good mental health among younger adults, particularly men. Results for adults 65 and older were mixed and often not statistically significant.

The main analyses did not find a consistent relationship between cannabis use and physical health in either age group. The authors caution that this does not mean cannabis use carries no physical health risks.

“Although medical use of marijuana has numerous benefits, the cannabis industry, just like the pharmaceutical industry or the medical-device industry, tends to emphasize all the advantages of their products without a full assessment of the potential consequences,” said French. “Objective academic researchers and other scientists without a predetermined agenda can provide unbiased analyses of the true costs and benefits.

“As articulated in the paper, we are presenting our findings without advocating for a particular policy or law. Policymakers can use our results to formulate more informed initiatives that consider the full spectrum of pros and cons associated with cannabis use.”

By Blair S. Walker

Source: University of Miami

Categories : Mental Health Substance UseTags :

Study: Adolescent Cannabis Use Linked to Doubling Risk of Psychotic and Bipolar Disorders

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Adolescents who use cannabis could face a significantly higher risk of developing serious psychiatric disorders by young adulthood, according to a large new study published in JAMA Health Forum. The longitudinal study followed nearly half a million adolescents ages 13 to 17 through age 26 and found that past-year cannabis use during adolescence was associated with a significantly higher risk of incident psychotic (doubled), bipolar (doubled), depressive and anxiety disorders.

The study was conducted by researchers from Kaiser Permanente, the Public Health Institute’s Getting it Right from the Start, the University of California, San Francisco and the University of Southern California, and was funded by a grant from NIH’s National Institute on Drug Abuse (R01DA0531920).

The study analysed electronic health record data from routine paediatric visits between 2016 and 2023. Cannabis use preceded psychiatric diagnoses by an average of 1.7 to 2.3 years. The study’s longitudinal design strengthens evidence that adolescent cannabis exposure is a potential risk factor for developing mental illness.

“As cannabis becomes more potent and aggressively marketed, this study indicates that adolescent cannabis use is associated with double the risk of incident psychotic and bipolar disorders, two of the most serious mental health conditions,” said Lynn Silver, MD, program director of the Getting it Right from the Start, a program of the Public Health Institute, and a study co-author.

The evidence increasingly points to the need for an urgent public health response — one that reduces product potency, prioritises prevention, limits youth exposure and marketing and treats adolescent cannabis use as a serious health issue, not a benign behaviour. 

Lynn Silver, MD, Program Director, PHI’s Getting it Right from the Start

Cannabis is the most used illicit drug among U.S. adolescents. The Monitoring the Future study shows use rising with grade level — from about 8% in 8th grade to 26% in 12th grade — and according to the 2024 National Survey on Drug Use and Health, more than 10% of all U.S. teens aged 12 to 17 report past-year use. At the same time, average THC levels in California cannabis flower now exceed 20%, far higher than in previous decades, and concentrates can exceed 95% THC.

Unlike many prior studies, the research examined any self-reported past-year cannabis use, with universal screening of teens during standard pediatric care, rather than focusing only on heavy use or cannabis use disorder.

“Even after accounting for prior mental health conditions and other substance use, adolescents who reported cannabis use had a substantially higher risk of developing psychiatric disorders — particularly psychotic and bipolar disorders,” said Kelly Young-Wolff, PhD, lead author of the study and senior research scientist at the Kaiser Permanente Division of Research.

This study adds to the growing body of evidence that cannabis use during adolescence could have potentially detrimental, long-term health effects. It’s imperative that parents and their children have accurate, trusted, and evidence-based information about the risks of adolescent cannabis use.

Kelly Young-Wolff, PhD, Lead Study Author and Senior Research Scientist, Kaiser Permanente Division of Research

The study also found that cannabis use was more common among adolescents enrolled in Medicaid and those living in more socioeconomically deprived neighbourhoods, raising concerns that expanding cannabis commercialisation could exacerbate existing mental health disparities.

Source: Public Health Institute

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Study Untangles the Complex Relationship Between Cannabis and Binge Drinking

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Binge drinking is most common among younger adults, and using cannabis during late adolescence or early adulthood is known to increase the risk of engaging in binge drinking. Now, new research from the Arizona State University Department of Psychology shows that this increase in risk of binge drinking from cannabis use varies with age, peaking around age 20.

“We found that during ages 18 to 20, cannabis motivates people to binge drink more often, while later in adulthood, around age 24, it motivates them to binge drink less. This dichotomy has consequences for prevention and treatment efforts,” said Jack Waddell, assistant professor of psychology at ASU and first author on the study.

The study used cannabis use and alcohol consumption data from the National Consortium on Alcohol and Neurodevelopment in Adolescence, a long-term study of over 500 participants with sites in California, Oregon, North Carolina and Pennsylvania. The work was published in Alcohol Clinical and Experimental Research.

Not just one substance

Waddell described the interaction of cannabis use and alcohol consumption as a complex relationship. 

He has previously found that individuals who use both alcohol and cannabis report higher rates of substance use disorder than those who use just one. Yet, he has also found that many individuals who use both alcohol and cannabis perceive using them together as being protective against some of the negative consequences of excessive drinking.

In the current study, he and his collaborators expected using cannabis to consistently increase the likelihood of the study participants engaging in binge drinking, not for it to flip from enabling excessive drinking in late teens and early 20s to blunting it around age 24.

“People are reducing their binge drinking but they’re switching to cannabis. This can be viewed positively from a harm-reduction standpoint, but it is important to understand that there are still a lot of risks associated with cannabis use,” Waddell said.

Digging into the dynamics of substance use

Waddell wants to understand how people end up using more than one substance, and to do this, he plans to study how people think about and use substances on a day-to-day basis.

“What is it that motivates the transition from using one substance to more than one? Is it someone’s affective experiences – their emotions and moods – whenever they’re using alcohol or cannabis that makes them want to add the other? Is it the social environment?” he asked.

Going forward, Waddell plans to use technology-enhanced momentary assessments, which are questionnaires or check-ins delivered by push notification on an app or text message, to study people’s behavior in the moment. 

Having a finer-grained level of access to how different kinds of substance use interact with and influence each other will lead to better treatment and prevention strategies.

Categories : Obstetrics & Gynaecology Substance UseTags :

Study Explores How Prenatal Cannabis Exposure May Affect Foetal Brain Development

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Researchers at UTHealth Houston are examining the biological effects of prenatal cannabis exposure and its potential impact on foetal brain development. Supported by a $3.7 million grant from the National Institutes of Health and the National Institute on Drug Abuse, the study aims to improve screening tools, public health guidance, and prenatal care strategies for pregnant people who use cannabis.

Led by Laura Goetzl, MD, MPH, a professor in the Department of Obstetrics, Gynecology, and Reproductive Sciences at McGovern Medical School at UTHealth Houston, the five-year grant will fund the study, “Foetal neuronal extracellular vesicle biomarkers of in-utero effects of maternal cannabinoid use and human foetal brain development and neurobehavioral outcomes.”

“In recent years, cannabis use among pregnant women has increased, either recreationally or to help relieve nausea and vomiting during pregnancy,” Goetzl said. “Despite this rise, the effects on a baby’s brain are not well understood. Our hope through this research is that we can better identify risk factors and help health care providers give expecting mothers the best possible guidance.

The study will explore early biological signs, or biomarkers, to show how cannabis exposure influences a baby’s developing brain.

“During pregnancy, small bubbles called neuronal extracellular vesicles travel from the foetus into the mother’s bloodstream,” Goetzl said. “Through studying these small particles, we hope to gain valuable insight into foetal brain development without invasive testing.”

In collaboration with the University of Colorado, the research study will focus on how prenatal cannabis exposure may influence brain growth and neurobehavioral outcomes in children, including their potential for developing attention-deficit/hyperactivity disorder (ADHD) or autism later in life.

The project is supported by the National Institute on Drug Abuse of the National Institutes of Health under award number R01DA060319.

Source: UTHealth Houston

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Flavoured Marijuana Vapes Becoming New Face of Teen Drug Use, Sparking Addiction Fears

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Flavoured marijuana vaping is now the most common form of use among American teenagers who vape cannabis, according to new findings from the University of Michigan.

The research, published in the Journal for Adolescent Health, found particularly sharp increases among younger teens between 2021 and 2024. Among eighth graders who vaped marijuana, the percentage using flavoured solutions jumped from 47% in 2021 to 63% in 2024. The trend was similar for older students, with use climbing from 41% to 53% for 10th graders and from 36% to 50% for 12th graders.

“The findings suggest that these products are gaining traction among youth; in fact, since the pandemic onset in 2020 youth appear to be turning toward these products while reducing their use of all other drugs,” said Richard Miech, principal investigator of the Monitoring the Future study at U-M’s Institute for Social Research.

The overall percentage of marijuana users who chose to vape the drug also grew over the study period. Among eighth graders who had used marijuana in the past 12 months, the percentage who vaped it increased from 48% to 57%. In 10th grade, the number went from 60% to 66%, and among 12th graders, it rose from 58% to 67%.

“Flavoured vaping solutions offer a discreet mode of cannabis use, with flavours apparently enhancing their appeal,” Miech said. “The study results suggest that a growing proportion of youth find the newly available flavours – especially fruit flavours – more attractive than the standard cannabis taste.

“Vaping does not produce the distinctive odor that comes from smoking cannabis, and vaping devices can be quickly concealed if an authority figure appears unexpectedly.”

More addictive?

This increase in those who vaped highlights growing public health concerns about changing patterns of substance use among teens.

“As for health consequences for cannabis use, one of the most potentially serious is addiction,” Miech said. “Should cannabis use become more popular among youth in future years, then a greater number will end up with an addiction that can impair their social and academic life. Many people may not realize that more adolescents meet the criteria for cannabis use disorder than for alcohol use disorder, with 5% affected by cannabis compared to 3% for alcohol.”

These results point to flavored marijuana vaping solutions as a critical area for future research and policy development. The study’s authors suggest that these findings underscore the need for targeted policies, interventions and educational campaigns to address and mitigate this escalating concern among young people.

“Our survey includes questions on both cannabis’s perceived risk and its social acceptability,” Miech said. “Interestingly, perceived risk among adolescents actually increased over the study period from 2021-24, and social acceptability has gone down. That being said, our questions so far have been about cannabis use in general, and not flavoured cannabis solutions, which students may view differently.”

Would restricting flavoured vapes work?

Recent trends in adolescent cannabis vaping raise concerns about the best way to protect youth. Restricting flavors may seem like an easy solution, but it is by no means a guaranteed success, researchers said.

Teens who seek flavored cannabis products could easily shift to unflavored options or return to smoking cannabis in traditional forms. At the same time, adults in states with legal cannabis may resist limits on flavor choices, and industry lobbying could block such policies.

“An alternative approach to restricting supply of cannabis flavours is to restrict demand,” Miech said. “That is, to reduce teens’ interest and willingness to use cannabis, including flavoured vaping solutions. A demand reduction approach has been very effective for cigarettes.”

Evidence from previous studies on cigarette use supports this approach. In 1998, 35% of 12th graders had used cigarettes in the past month. By 2024, that number dropped to 3%. Cigarettes remained legal and available, but broad-based media campaigns, public education and tighter rules on marketing to youth drove the change.

Source: University of Michigan

Categories : Respiratory Diseases Substance UseTags :

Inhaling Cannabis May Greatly Increase Risk of Lung Disease

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For those looking to reduce their chances of developing lung disease, say experts at UC San Francisco, then it may be smart to avoid inhaling cannabis.

A new study in the Journal of General Internal Medicine found that inhaling marijuana every day is associated with a 44% increased chance of developing asthma. It also increases the odds of developing a common set of lung diseases known as chronic obstructive pulmonary disease (COPD) by 27%.

The risk of COPD, which includes emphysema and chronic bronchitis, may be understated. The disease takes decades to develop, and the researchers did not have detailed information on how long people in the study had been using cannabis.

Researchers defined “inhaling” as smoking, vaping, and so-called “dabbing,” which involves breathing in the vapors of concentrated marijuana. The study found an association between elevated risks to a person’s lungs and doing any of those things with cannabis even for those who had never smoked cigarettes.

For those who never smoked cigarettes, inhaling marijuana every day was linked to a 51% increased likelihood of developing asthma. The association with COPD was also elevated, but it was not statistically significant.

The study is the largest yet to examine the association between inhaling cannabis and risks to respiratory health among people who have not smoked cigarettes. Of the 380 000 adult participants, nearly 222 000 had never smoked tobacco. The data comes from the Behavioral Risk Factor Surveillance System, a national survey by the Centers for Disease Control and Prevention (CDC).

Experts say the broad legalization of marijuana across much of the country and the perception that it is healthier than tobacco has led people to minimize the risks.

“The message about smoking tobacco being bad for you has gotten out there, but for cannabis, it’s much less clear,” said Alison Rustagi, MD, PhD, assistant professor at UCSF and first author of the paper.

“If people are looking to reduce their likelihood of developing a chronic lung disease, they should not start using cannabis,” she said. “And if they already smoke cannabis, they should do it less often.”

Source: University of California – San Francisco

Categories : Mental Health Substance UseTags :

Poor Mental Health Can Be Worsened by Cannabis Use

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New research from the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King’s College London, in partnership with the University of Bath, has found that the reasons why a person chooses to use cannabis can increase their risk of developing paranoia.

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The use and potency of cannabis is increasing worldwide, and dependence and cannabis-induced psychosis are also greatly increasing as a result, especially in North America. Two new research papers, both using data from Cannabis & Me – the largest survey of its kind – have identified key risk factors associated with the more severe forms of paranoia in cannabis users.

The first study, published in BMJ Mental Health, explored the relationship between why people first started using cannabis, and how this affected their subsequent use.

3389 former and current cannabis users aged 18 and over responded to a survey examining their reasons for first and continued use, their weekly consumption of cannabis in THC units, and their mental health.

Researchers established several key findings. Respondents who first started using cannabis to self-medicate an illness, including physical pain, anxiety, depression, or because they were experiencing minor psychotic symptoms, all demonstrated higher paranoia scores.

This was in contrast to those respondents who tried cannabis for fun or curiosity, or with their friends, who reported the lowest average paranoia and anxiety scores.

Dr Edoardo Spinazzola, a Research Assistant at King’s IoPPN and the study’s first author said, “This research suggests that using cannabis as a mean to self-medicate physical or mental discomfort can have a negative impact on the levels of paranoia, anxiety, and depression. Most of these subgroups had average scores of depression and anxiety which were above the threshold for referral to counselling.”

Respondents were also asked to provide data on the frequency and strength of the cannabis they were using so that researchers could track their average weekly consumption of Tetrahydrocannabinol (THC) – the principle psychoactive component of cannabis.

The researchers found that the average respondent consumed 206 units of THC a week. This might equate to roughly 10-17 ‘joints’ per week, if the user was consuming an expected 20% THC content that is standard for the most common types of cannabis available in London.

However, respondents who started using cannabis to help with their anxiety, depression, or in cases where they started due to others in their household who were already using cannabis, reported on average 248, 254.7, and 286.9 average weekly THC units respectively.

Professor Tom Freeman, Director of the Addiction and Mental Health Group at the University of Bath and one of the study’s authors said, “A key finding of our study is that people who first used cannabis to manage anxiety or depression, or because a family member was using it, showed higher levels of cannabis use overall.

“In future, standard THC units could be used in a similar way to alcohol units – for example, to help people to track their cannabis consumption and better manage its effects on their health.”

In a separate study, published in Psychological Medicine, researchers explored the relationship between childhood trauma, paranoia and cannabis use.

Researchers used the same data set from the Cannabis & Me survey, with just over half of respondents (52 per cent) reporting experience of some form of trauma.

Analysis established that respondents who had been exposed to trauma as children reported higher average levels of paranoia compared to those who hadn’t, with physical and emotional abuse emerging as the strongest predictors.

Researchers also explored the relationship between childhood trauma and weekly THC consumption. Respondents who reported experience of sexual abuse had a markedly higher weekly intake of THC, closely followed by those who reported experiencing emotional and physical abuse.

Finally, the researchers confirmed that the strong association between childhood trauma and paranoia is further exacerbated by cannabis use, but is affected by the different types of trauma experienced. Respondents who said they had experienced emotional abuse or household discord were strongly associated with increased THC consumption and paranoia scores. Respondents reporting bullying, physical abuse, sexual abuse, physical neglect and emotional neglect on the other hand did not show the same effects.

Dr Giulia Trotta, a Consultant Psychiatrist and Researcher at King’s IoPPN and the study’s first author said, 

“We have not only established a clear association between trauma and future paranoia, but also that cannabis use can further exacerbate the effects of this, depending on what form the trauma takes.

“Our findings will have clear implications for clinical practice as they highlight the importance of early screening for trauma exposure in individuals presenting with paranoia.”

Professor Marta Di Forti, Professor of Drug use, Genetics and Psychosis at King’s IoPPN, Clinical Lead at the South London and Maudsley NHS Foundation Trust’s Cannabis Clinic for Patients with Psychosis, and the senior author on both studies said, “There is extensive national and international debate about the legality and safety of cannabis use.

“My experience in clinic tells me that there are groups of people who start to use cannabis as a means of coping with physical and emotional pain. My research has confirmed that this is not without significant further risk to their health and wellbeing, and policy makers across the world should be mindful of the impact that legalisation , without adequate public education and health support, could have on both the individual, as well as on healthcare systems more broadly.”

Source: King’s College London

Categories : Mental Health Substance UseTags :

Cannabis Potency May Be Driving a Rise in Schizophrenia

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A new article published in the Canadian Medical Association Journal warns of the mental health dangers stemming from the increasing potency of cannabis. In Ontario, there has been a more than 14-fold increase in risk for visiting the emergency department for cannabis-related schizophrenic disorders. After a cannabis-induced psychotic episode, cessation of cannabis use is necessary to reduce the risk of relapse, and in severe cases, antipsychotics may be needed.

“Cannabis from the 2000s is not the same as in 2025,” said coauthor Dr Nicholas Fabiano, MD, resident and researcher with the Department of Psychiatry, University of Ottawa, Ottawa, Ontario. “THC content has increased by 5 times. This is likely a significant driver in the increasing link between cannabis use and schizophrenia.”

  1. Cannabis potency is increasing — The concentration of tetrahydrocannabinol (THC) has increased fivefold in the last 20 years in Canada from about 4% to 20% in most legal dried cannabis.
  2. High-potency and regular cannabis use is linked to increased risk of psychosis — The risk of psychosis is increased in people using high-potency THC (more than 10% THC), people using it frequently, and those who are younger and male. A history of mental disorders (depression, anxiety, etc) also appears to increase the risk.
  3. Cannabis-induced psychosis and cannabis use disorder increase the risk of schizophrenia — A recent study of 9.8 million people in Ontario found a 14.3-fold higher risk of developing a schizophrenia-spectrum disorder in people visiting the emergency department for cannabis use and a 241.6-fold higher risk from visits for cannabis-induced psychosis.
  4. Treatment requires stopping cannabis and taking medication — Continued use of cannabis after a first episode of cannabis-induced psychosis is linked to greater risk of returning symptoms. Antipsychotic medication can help people with severe and prolonged symptoms.
  5. Behavioural options may help with cannabis cessation — Motivational interviewing or cognitive behavioural therapy by a physician or psychologist can help build skills to resist cravings and follow treatment recommendations.

Source: EurekAlert!

Categories : Cancer Substance UseTags :

Oral Cancer Risk is Greatly Elevated in Cannabis Use Disorder

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A recent study by researchers at the University of California San Diego School of Medicine has found that individuals with cannabis use disorder (CUD) are more than three times more likely to develop oral cancer within five years compared to those without CUD. The study, published in Preventive Medicine Reports, highlights the potential long-term health risks associated with problematic cannabis use.

In 2022, 17.7 million people in the US reported daily or near-daily cannabis use. Though CUD requires a formal diagnosis and not all cannabis users develop the disorder, recent research suggests that as many as 3 in 10 cannabis users will develop CUD.

“Cannabis smoke contains many of the same carcinogenic compounds found in tobacco smoke.”

As cannabis becomes more widely available and socially accepted, it is essential to understand its potential health risks. While many consider cannabis to be safer than other drugs, such as tobacco and alcohol, there are still many unknowns about the health impacts of cannabis, particularly how the drug influences cancer risk. The new study sought to determine the relationship between CUD and oral cancer, for which tobacco smoking is known to be a significant risk factor.

“Cannabis smoke contains many of the same carcinogenic compounds found in tobacco smoke, which have known damaging effects on the epithelial tissue that lines the mouth,” said Raphael Cuomo, PhD, associate professor in the Department of Anesthesiology at UC San Diego School of Medicine and member of UC San Diego Moores Cancer Center. “These findings add to a growing body of evidence suggesting that chronic or problematic cannabis use may contribute to cancer risk in tissues exposed to combustion products.”

By analysing the electronic health records from over 45 000 patients, of whom 949 developed CUD, Cuomo found:

  • After adjusting for age, sex, body mass index and smoking status, people had a 325% higher likelihood of contracting oral cancer within five years compared to those without CUD.
  • Tobacco smokers with CUD were 624% more likely to contract oral cancer within five years compared to tobacco smokers without CUD.

Because the association between CUD and oral cancer remained even after controlling for smoking status, and because CUD was associated with greater oral cancer risk even when the analysis was restricted to smokers, the researchers hypothesise that there may be other factors underlying this risk in addition to smoke inhalation. For example, THC, the active compound in cannabis, is known to have immune-suppressing effects, which may contribute to increased cancer risk.

While more research is needed to fully explain the association between cannabis and oral cancer, the study’s results have immediate implications for cancer screening practices and public health messaging. In particular, the findings emphasise the need for further research on the long-term effects of cannabis use and the importance of integrating oral health awareness into substance use disorder treatment and counselling.

Source: University of California – San Diego