Since the first state to legalize recreational weed was announced, a lot of controversial information about the effects of weed on your health has appeared out there. While many scientists and experts agree that marijuana is a relatively safe substance to temporarily alleviate the symptoms of certain medical conditions, the benefits of recreational cannabis use remain poorly understood.
A report titled “The health and social effects of non-medical cannabis use”, recently published by the World Health Organization (WHO), explains some of the health consequences of recreational marijuana use, especially by young people. Marijuana experts assessed the risks of physical and mental impairments in pot smokers based on the last two decades of cannabis research.
Because teenagers are more likely to use cannabis and engage in risky patterns of use, it was vital to take a closer and more comprehensive look at the ways that substance could affect them. Today, the issue of marijuana use is given a lot more attention than even a couple of years ago. The WHO experts tried to summarize the most significant of the latest evidence on the adverse health effects of cannabis use for the last twenty years by publishing the report. On the basis of the current review by the scientists from every corner of the world, the following conclusions about the known effects of cannabis use were made.
Among the short-term effects of cannabis use, there may be: reduced motor coordination, loss of the ability to plan, organize, and make decisions; problems with verbal expression; anxiety, paranoia, hallucinations, panic attacks; increased blood pressure and heart rate, acute cardiovascular complications, and other symptoms.
The severity of the side effects of cannabis depends on the dose, frequency of consumption, and various genetic and environmental factors. Most of the cognitive short-time effects fade within a few hours after consumption.
Weed was found to produce acute bronchial effects, including bronchial constriction and dilation, the severity of which depends on the dose of THC in the substance consumed. Moreover, certain studies showed that the risk of experiencing myocardial infarction after smoking weed for patients with a recent heart attack increased by up to four times compared to the users with no history of infarctions.
The amount of evidence to the negative effects of marijuana on driving is increasing, but it is still insignificant compared to the evidence on the effects of alcohol.
Among the potential mental effects of marijuana, researchers point at cognitive impairment, mental illnesses, suicidal tendencies, and drug dependence.
Regular cannabis use is associated with experiencing psychotic symptoms, especially when there is a personal or family history of mental disorder. Long-term, heavy use of weed with a high THC content may also increase the risk for psychosis and schizophrenia by up to five times.
Swedish experts who have been researching a dose-response relationship between the frequency of marijuana use at the age of 18 and the risk of mental problems estimated that 13 percent of cases of schizophrenia would have been averted if none of the study participants had used the drug. Another meta-analysis also confirmed that psychotic symptoms were more frequent in regular cannabis users that in non-users.
Persons with cannabis-use disorders were also found to have higher rates of depression, as well as eating and personality disorders.
Another interesting study was published in 1994; it reported that regular marijuana users had a poorer cognitive performance, including deficits in verbal learning, attention, and memory than the non-using controls. Since then, it has been proven that the substance may be associated with verbal impairment and lower IQ scores. Teenagers who use cannabis often showed poor school performance and experienced social adversity during adolescence. However, the findings that imply cannabis may cause IQ decline are not enough to declare that marijuana use is the only reason for poor cognitive performance.
If you have read our publication about the effects of recreational cannabis use on mental health, you already know that as for the suicide risk, studies on marijuana use and suicide cases provided mixed results: while some scientists reported a positive correlation between marijuana use and the number of suicides, others said that they were not able to find any.
Many people are also concerned about the safety of cannabis, particularly the relationship between cannabis consumption and increased risk for cancer.
Numerous studies showed that THC itself was not carcinogenic, which cannot be said about cannabis smoke. The scientists suggest some negative effects of marijuana on lungs. Like cigarette smoking, marijuana smoking may cause cancer of the lung, tongue, mouth, esophagus, bladder, cancers of the pancreas, kidneys, stomach, testicular cancer, and so on. However,
researchers also raise suspicion in the fact that using marijuana may cause upper respiratory tract cancers although providing limited support to the hypothesis. In most studies, cannabis users also smoked tobacco or used alcohol or other drugs, so the quality of such case reports cannot be considered sufficient, and the evidence to the risk for cancers among marijuana smokers is not consistent.
The study of 1997 found an elevated risk for prostate cancer among cannabis smokers, but the experts believe that other lifestyle factors can be a possible explanation for the finding because AIDS-related deaths were higher among smokers in the study. You can find more information about the link between cannabis use and the risk of cancer in our previous review.
According to the report, youngsters who use cannabis regularly are about twice as likely to experience cognitive impairments as the adolescents who do not use the substance. Long-term, heavy drug use was proven to cause enduring neuropsychological problems that last beyond the period of acute intoxication.
As we wrote in considerable detail previously, a recent WHO review showed that some preventive programs had a special beneficial or likely beneficial impact on marijuana use, reduced the harm associated with the drug use by young people, and created a positive environment.
Most of the preventive methods considered in the report had an impact on problematic behaviors, such as tobacco, alcohol, and drug use.
Particularly, family preventive strategies—the widely adopted intervention that involved training for children, their parents, and relatives—have been found to be more effective that youth-only programs and social intervention. Such methods provided young people with services specific to their particular needs, thus being less stigmatizing and simultaneously addressing different levels of risk.
The social influence interventions (life skills lessons, different activities to boost self-esteem, and normative educational methods) could potentially reduce cannabis use. Furthermore, interactive activities have shown to be more effective than those only based on lectures, and programs based on a combination of social skills and social influence approaches had good results in preventing the use of both marijuana and other drugs.
As for marijuana dependence, WHO experts also found evidence to support the simultaneous use of several approaches: for example, a combination of motivational enhancement therapy using stimulus control and providing specific rewards and family therapy measures would give better results than waiting list control.
Although treatment has been found to reduce the severity of cannabis-related impairments and the frequency of use, clinical trials of cognitive behavioral therapy for the substance showed that only a small number of heavy users remained abstinent 6-12 months after the treatment.