Sales Hotline +1 (855) 904-4090
Great! 5167 Reviews on
  • Secure Payment
  • Discreet Packaging
  • Buy 2+ Products & Get FREE SHIPPING!
  • High Quality Seeds for Sale

Long-Term Health Concerns

Mar 12, 2020
The Latest Cannabis Research

Long-Term Health Concerns

Marijuana is widely regarded by those in the cannabis community as one of the safest drugs around. Occasional use doesn’t seem to place consumers at any risk of overdose, and health complications like marijuana allergies or the exacerbation of respiratory symptoms are few and far between. That doesn’t mean it’s completely safe for long-term, heavy use, though. After all, marijuana smoke still contains some of the same chemical compounds as tobacco smoke, and everyone knows that smoking presents serious long-term health risks.

The question is, how does marijuana compare? Unfortunately, there’s much less epidemiological data on the long-term health impacts of marijuana in developed nations due to a near-total ban on both use of and research into marijuana that was in place for most of the 20th century. This article will evaluate what evidence is available on the long-term health impacts of marijuana to give a better idea of its relative safety and what frequent users should expect.

Long-Term Cannabis Use and Lung Health

Since most cannabis consumers have historically smoked marijuana instead of ingesting it orally, lung health is a good place to start. Almost anyone who watches or reads the news has likely been exposed to at least a few alarmist articles about cannabis smoking and lung health, especially since opponents of cannabis legalization search far and wide to find studies that prove their points. It’s important to note that most studies on the impact of smoke on lung health do not control adequately for co-occurring factors such as tobacco use.

Some researchers have produced data that suggests marijuana smoke is harmful to the lungs. There is still much debate surrounding this subject in scientific circles. Some scientists believe it does, while others have found that the impact of marijuana smoke on the lungs, even after years of frequent exposure, is negligible. More research will be required before a consensus can be reached, but here’s what researchers on both sides of the argument know so far.

Evidence of Increased Incidences of Respiratory Disease

One academically viable 1993 study performed by the Kaiser Permanente Center for Health Research showed that daily marijuana smokers who did not use tobacco had a 19% higher risk of developing respiratory diseases. The study evaluated the health and consumption habits of 452 marijuana-only smokers to 450 control subjects. The researchers found that despite controlling for tobacco use, there might still have been some unknown factors contributing to the study’s findings.

Namely, the marijuana-smoking subjects drank more heavily than the control subjects. The researchers believe this confounding factor was because the heaviest drinkers among non-smokers of marijuana were excluded from participation due to their tobacco use. They also made no effort to control for the use of other substances, including alcohol, opiates, cocaine, methamphetamines, and prescription drugs.

The Kaiser study found that the highest incidences of respiratory disease occurred in cannabis users who had been smoking for less than ten years. It could be that cannabis smokers who develop adverse reactions quit earlier than those who are less susceptible to respiratory disease, although there is no concrete evidence to back this up.

The same study found that daily marijuana users had a 30% higher risk of incurring injuries in daily life. The intoxicating effects of marijuana may create cognitive symptoms that make people prone to injury, but it is also possible that confounding factors like alcohol and other drug use play a role in increasing consumers’ risk of personal injury.

Evidence Against Worsening Lung Function

At least one more recent longitudinal survey of long-term cannabis users performed in the United States produced conflicting results. The study evaluated lung function as a measure of FEV1, or exhalation capacity, decline in adults who used marijuana using data collected by the U.S. National Health and Nutrition Examination Study. The researchers found no evidence of statistically significant FEV1 decline, even in participants who reported up to 20 years of marijuana smoking. However, researchers do not deny that frequent, long-term marijuana users report some bronchitis symptoms.

What About Lung Cancer?

Marijuana smoke contains some of the same chemical components as tobacco smoke, which means it can have short-term adverse effects on the lung and throat. What does that mean in terms of lung cancer risk, though? The jury is still out, but as research into marijuana expands, so does the knowledge of its inherent health risks.

Researchers have already determined that the psychoactive and therapeutic components of marijuana, such as THC, CBD, and its other cannabinoids, are not carcinogenic. The dangerous chemical components found in marijuana smoke are the byproducts of leaf combustion. They are found in all combusted plant material.

Like tobacco smoke, marijuana smoke contains polycyclic aromatic hydrocarbons (PAHs). PAHs are believed to be a major contributing factor in smoking-related cancers and have been proven to be carcinogenic.

Despite the presence of PAHs in marijuana smoke, the results of actual research studies on the impact of marijuana smoking on lung cancer development have not been as damning as one might assume. The first large-scale, scientifically viable study of lung cancer in marijuana smokers, completed in 2005 by doctors Mia Hashibe and Paul Tashkin from the University of California, found no correlation between exposure to marijuana smoke and lung cancer, even in long-term heavy users. Much to the researchers’ surprise, the rates of lung cancer among short-term users were lower than they were for non-users.

At first glance, these results may appear to conflict with other medical research studies, most notably one well-known study performed in New Zealand that correlated chronic, heavy marijuana smoking with increased lung cancer risk. What’s notable, though, is while this study received a lot of media attention, what the media failed to report was that only 9 of the 79 participants had no lifetime history of tobacco use. The media also failed to report that according to this same study, occasional and moderate cannabis smokers were at a decreased risk of developing lung cancer compared to the control subjects.

The presence of THC may explain the lower rates of lung cancer among short-term users and lack of epidemiological evidence that marijuana smoking causes lung cancer in the long term. One animal study performed at Harvard indicated that THC blocks the epidermal growth factor known to promote cancer cell growth in small-cell lung cancers. The researchers behind this study even suggested that THC and other cannabinoids be evaluated as possible therapies for suppressing cancer cell growth and metastasis.

The Bottom Line on Marijuana and Lung Health

The jury is still out on whether long-term, heavy marijuana smoking is linked with poor lung health outcomes, and few studies, to date, have used scientifically rigorous research methods. Until more longitudinal studies are performed that account for confounding factors like tobacco use and other drug use, it would be irresponsible to say definitively that smoking marijuana does not contribute to an elevated risk of lung cancer and respiratory disease. So far, no studies have shown a correlation between short-term or long-term moderate use, though, and researchers have determined with relative certainty that marijuana’s psychoactive components do not pose a risk to lung health.

The best way for health-conscious marijuana consumers to address the potential risks associated with smoke inhalation, more generally, is to switch to alternative methods of consumption such as ingesting edibles, applying topical oils, or vaping. As with marijuana smoking, the benefits and risks of vaping are still widely debated.

Benefits and Risks of Vaping Marijuana

Vape pens have gotten a bad rap in the past year, which is understandable. As of February 18, 2020, the CDC reported a total of 2,807 vaping-related lung injuries and 68 deaths. Some states have restricted the sale of vape pens and cartridges, and the CDC has launched an awareness campaign to alert teenagers to the potential dangers of vaping.

That sounds bad, but is it really the marijuana that’s to blame? The short answer is no. More recent studies of vaping and popcorn lung have determined that the respiratory disease is caused by vitamin E acetate inhalation. Vitamin E acetate is found in both THC and nicotine vape oils, and as the recent development of diseases and deaths have shown, it shouldn’t be.

Are Vape Oils Inherently Dangerous?

Vape oils are not supposed to contain toxins, contaminants, or substances like vitamin E acetate that are safe when consumed orally but not intended for inhalation. Licensed cannabis vape oil producers are regulated to prevent them from including suspicious additives and tested for potential contaminants. Illegal, black market vape cartridges, on the other hand, are subject to no testing and are much more likely to contain dangerous substances.

Most cases of vaping-related respiratory disease have occurred after consumers use illicit products. Using products that have not been produced by licensed, regulated manufacturers is inherently unsafe.

Differences Between Vape Pens and Traditional Vaporizers

Vape pens are designed to burn only specialized vape oils. Traditional marijuana vaporizers, including portable vaporizers, can be used to vaporize ground-up marijuana. While vape oils can contain contaminants that are dangerous to consumers’ health, vaporizing dried marijuana flower does not pose the same health risks.

If consumers purchase and vaporize marijuana from a licensed dispensary or grow their own marijuana that it is free from mold and chemical contaminants, they don’t have to worry about respiratory diseases associated to vape pens. Most experts believe that vaporizers, which heat marijuana to release its psychoactive and therapeutic compounds without combustion-producing PAHs, is a healthy alternative to smoking cannabis.

Long-Term Cannabis Use and Heart Health

Vaping may also be better for heart health, especially with long-term, frequent consumers of marijuana. Smoke inhalation, in general, is known to compromise cardiovascular function. It dilates blood vessels and raises the resting heart rate, which can cause the heart to work harder. This can be a problem for consumers who already have heart problems, as it can raise their risk of heart attacks, strokes, arrhythmias, and other cardiovascular diseases.

There has not been much scientifically rigorous research to date on the effects of cannabis consumption on heart health. However, what information is available generally indicates that consumers without existing heart problems will not increase their risk of adverse cardiovascular events by smoking marijuana. The best way for consumers who struggle with heart disease to minimize their risk is to switch from smoking to vaporizing ground marijuana, or consuming edibles.

It’s important to note that the negative impacts of cannabis smoke, and other types of smoke, on cardiovascular health are not limited to smokers, themselves. Secondhand smoke can also be dangerous. Smokers should consume responsibly and avoid smoking in confined spaces with non-smokers who know they have an elevated risk of heart disease.

Long-Term Cannabis Use and Mental Health

The myths and misconceptions surrounding marijuana’s effects on mental health date back almost a century, to the very beginning of marijuana prohibition. Today’s consumers need only look back on 1930s propaganda like Reefer Madness to see exactly how serious some of the negative allegations about marijuana use and mental health have been.

While today’s more educated audiences tend to view it as satire, the film’s producers were dead serious. They genuinely believed that using marijuana made people violent and psychotic. Even today, many opponents to legalizing marijuana cite connections between increased marijuana use and adverse mental health events. Unfortunately, much of the research cited in well-known prohibitionist treatises rely on unsubstantiated claims, cherry-picked results, and just plain falsehoods, playing on modern Americans’ fears in the same way Anslinger and his colleagues did prior to the beginning of prohibition.

The question remains, though, is there anything to the allegations that long-term marijuana use adversely affects mental health? The answer is: it’s complicated.

People with Mental Illnesses More Likely to Use Cannabis

A 2013 study performed by Shauli Lev-Ran for the Centre for Mental Health and Addictions in Toronto, Canada, evaluated cross-sectional evidence from 43,000 participants and found that those who suffered from one or more mental health condition(s) were seven times as likely to use cannabis at least once per week. What is unclear is whether cannabis use contributes to the development of mental illness, or if those experiencing symptoms of mental illness are more likely to use cannabis to self-medicate. It’s somewhat of a chicken-or-the-egg scenario. Although Lev-Ran and others have continued to research the potential link between mental illness and marijuana use, no one has been able to prove a consistently definitive antecedent.

Cannabis Use and Depression

As a follow-up to his study in Toronto, Lev-Ran performed three additional studies that focused exclusively on depression. The first of them culled information from thousands of other studies on substance use and depression. The results showed that people who used cannabis had a higher long-term risk of developing symptoms of depression, but did not offer insight into other risk factors such as childhood trauma and genetic predisposition toward either substance-use or mental health disorders.

The second study focused on both users and non-users of cannabis who reported having never experienced symptoms of depression. The results showed that cannabis use or non-use did not impact participants’ risks of developing depression. However, additional data from the National Institute for Alcoholism Abuse and Alcoholism showed that people experiencing depression were more likely to use cannabis.

Lev-Ran’s final study evaluated the effects of cannabis on patients diagnosed with major depressive disorder. It investigated both potential risks and benefits, comparing depression symptoms in an experimental group that used cannabis to a control group that did not. The study’s results uncovered no significant differences between the two groups.

Cannabis Use and Anxiety Disorders

Anxiety disorders include things like generalized anxiety disorder (GAD), specific phobias, post-traumatic stress disorder (PTSD), and others. As with depression, the connection between anxiety disorders and cannabis use is complicated. Some marijuana consumers experience acute anxiety as a side-effect of excessive consumption, while others use cannabis products explicitly to treat their anxiety.

While most evidence of cannabis use causing anxiety is anecdotal, there have been some studies performed on patients already struggling with anxiety disorders and other mental health complaints that show long-term use can be detrimental. Some studies show that prolonged heavy use may worsen symptoms over time and lessen patients’ chances of successful remission, but results are mixed. Other studies show that marijuana is an effective long-term treatment, especially for PTSD.

The evidence of marijuana’s effectiveness as a treatment for PTSD is strong enough to have prompted Canada’s Department of Veterans Affairs (VAC) to offer up to three grams per day of medical cannabis free of cost to veterans diagnosed with the disorder. Marijuana is safer and far less addictive than other commonly prescribed anti-anxiety medications used in the treatment of PTSD like Valium and Ativan. It also has fewer negative side effects. It is not recognized as a cure for any mental health disorder but can be used as an effective treatment to reduce symptoms and make life more manageable for those suffering from severe anxiety disorders.

Cannabis Use and Psychotic Disorders

It’s a proven fact that patients with severe mental illnesses such as schizophrenia and bipolar disorder with psychotic symptoms are much more likely to self-medicate using drugs and alcohol. This is as true of marijuana as it is of alcohol, prescription drugs, and street drugs like heroin and cocaine. Many people have concluded based on this information that marijuana may be a contributing factor in schizophrenia and psychosis, more generally. The question is, does correlation equal causation?

There are a number of genetic and environmental factors known to contribute to schizophrenia and other psychotic disorders, and marijuana use is one of them. This appears to be particularly true when consumers genetically predisposed to schizophrenia are exposed to THC during childhood and adolescence. However, as schizophrenia risk is known to have a strong genetic component, it would be irresponsible to pretend this means marijuana use causes schizophrenia, especially if schizophrenic patients hadn’t started using marijuana until adulthood.

Some researchers believe cannabis may play a causal role in triggering initial psychotic episodes, while others believe people who are genetically predisposed to schizophrenia are also predisposed to marijuana use. The situation is further complicated by the fact that while THC exposure in adolescence may be a contributing factor in the development of schizophrenia, CBD has shown antipsychotic potential. Several studies have shown that CBD could have therapeutic benefits in the treatment of difficult-to-treat schizophrenia patients. What’s great is that CBD has substantially fewer negative side-effects than common antipsychotic medications do.

Cannabis and Substance Use Disorders

Research into cannabis and substance use disorders is also a mixed bag. The American Psychiatric Association’s (AMA) most recent diagnostic manual, the DSM-V, lists criteria for a condition called cannabis use disorder, which is like all other forms of substance use disorders. However, research has also shown that marijuana may help treat other forms of drug and alcohol addiction.

Unlike the prescription opioids typically used to treat chronic pain in conventional medical settings, marijuana is not physically addictive, and it does not pose any risk of overdose. This makes it preferable in some physicians’ eyes for use in treating conditions like chronic arthritis, cancer, and other sources of pain and inflammation. Long-term users of marijuana can develop a high tolerance for the drug, though, and some may develop symptoms of psychological addiction.

The Bottom Line

Marijuana has only been legal in industrialized countries for a few years, and in most places, it remains a controlled substance, which has prevented the development of research into the therapeutic effects and long-term health impacts of marijuana use. What research does exist has shown mixed results.

Most of the potential physical health risks of marijuana consumption can be mediated by choosing alternative methods of ingestion, but more research needs to be performed concerning potential links between marijuana use and mental health before anyone can make accurate generalizations about whether the benefits are worth the risks. For now, marijuana enthusiasts can always pay attention to how their consumption patterns affect their own mental and emotional states and draw their own conclusions.

Once an individual has assessed their mental and physical health, and concluded that cannabis consumption is a valuable lifestyle choice, they may wish to begin growing their own. To acquire souvenir cannabis seeds, please visit

Recent Posts
Is weed legal in California
Is weed legal in Florida
Check All Popular Posts

Buy Weed Seeds For Good Health

Buy Medicinal CBD Seeds Online

Related Posts
Is weed legal in Illinois

Is Weed Legal in Illinois?

Is Weed Legal in Illinois? Is weed legal in Illinois?   We’re happy to report that, yes, it's one of the states that has legalized mari...
Is weed legal in Georgia

Is Weed Legal in Georgia?

Is Weed Legal in Georgia?   Georgia - it’s home to the sweetest peaches and the birthplace of Coca-cola and wine. For years, this delig...
Is weed legal in California

Is Weed Legal in California?

Is Weed Legal in California? Content California marijuana laws Is buying cannabis legal in California? Can I grow my own cannabis in Califor...