Is marijuana harmless? A recent Times article was titled "Six Ways Science Says Marijuana May Hurt Your Health" and as the title suggest is marijuana harmful or is it relatively harmless? What is the reality? Below we share the article by Times along with commentary below each section. As you will see the Times article is misleading and doesn't cover the facts accurately.

Let's begin:

Boosters of marijuana legalization often speak about the relative harmlessness of the drug, especially when compared to alcohol and tobacco, which kill millions of people a year worldwide. But while the evidence suggests that pot is less damaging than some other legal drugs, the exact effects of marijuana on human health have not been well studied. Existing research is often limited in scope and rarely shows a clear causal connection.

The article indicates that very little research has been done and what has been done is limited. This simply isn't true. As of this post, there are over 20,000 studies on PubMed (PubMed is a free search engine accessing primarily the MEDLINE database of references and abstracts on life sciences and biomedical topics.) and nearly 13,000 studies on Cannabis (some of these studies may appear using both keywords so the total number will likely be lower). When searching the entire database there are over 165,000 and 149,000 hits (no pun intended) for cannabis and marijuana, respectively.

As we can see there have been numerous studies yet Times says, "…effects of marijuana on human health have not been well studied." While I do agree that more research should be done, this is by no means a low researched topic. On the topic of research part of the problem and why there are not more studies being done is because the United States Federal Government has severely restricted cannabis research. For research to happen for marijuana one must get the approval of the FDA, DEA, and NIDA (National Institute on Drug Abuse ). Both the DEA and NIDA have blocked research for those who are looking to study any positive effects of marijuana. Also the only source of marijuana that a federally funded study can use is marijuana provided from its official marijuana stockpile at the University of Mississippi. What is even more bizarre is that there are no other drugs that are required to jump through as many hoops are marijuana is required to do.

The article continues:

But there have been some worrying findings, especially considering the increasing use of marijuana by American adults. A paper published this year in Forensic Science International, for instance, described two rare deaths of young men that were attributed to heart conditions resulting from marijuana use.

With legalization taking place in Colorado and Washington State, more research will now be possible. For now, here is a tour of what has been documented so far about marijuana’s negative effects.

Below we will discuss these "worrying findings" and much more about what studies have shown.

1. It can interfere with learning

Marijuana interferes with the brain’s cannabinoid receptors, affecting cognitive functions such as movement, memory, and emotional control. A recent small study found that impairment in working memory occurs immediately after marijuana use. Subjects who received a higher dose of THC—marijuana’s main active chemical—took significantly longer to complete immediate recall and mental calculation tasks.

There is no secret that marijuana can cause short term impairment of cognitive functions. This is the very reason many people enjoy using marijuana. As the article stated this is also dependent on the dose. Low doses of marijuana may help a person relieve pain but not cause any impairment to that person. One person's "I cannot function at all" marijuana dosage is another's mild buzz. There is no exception to cognitive impairment; each person is different. A dose for one person may make them unable to perform a mental task while another may do just fine.

Another thing the article omits but sort-of implies is that the cognitive function impairment is immediate which means it is temporary. There have been studies that have shown that when a person abstains from marijuana use their cognitive scores are the same as a non-user.

The bottom line is if you are having to perform a cognitive task, be it for school, work or other reason, don't use marijuana or understand your dosage requirements and keep it at a low dose that treats your medical condition but doesn't interfere with your task at hand.

2. It can lead to dangerous driving

Pot impairs functions key to driving, including reaction time, hand-eye coordination and depth perception, a study by the University of Chicago reported. In the first full year after medical marijuana was legalized in Colorado, there was a 12% increase in traffic fatalities, according to data analysis by researchers at Columbia University. However, studies have not been able to provide consistent evidence to prove that the effects of marijuana cause an increased rate of collisions. According to a different study published in Accident Analysis and Prevention, the closest comparison to the culpability of accident when under the influence of marijuana is to a driver who has taken penicillin, anti-depressants or an antihistamine, which suggests marijuana’s effects have a nominal impact on accident risk. More research is needed.

Cannabis can cause impairment and you should never drive while stoned. However, some of the information presented is misleading. First the Times article indicated that the data came from Colorado while the fact is the authors used data for traffic fatalities in six states in 2010. What we must also consider is marijuana is fat soluble. You could use marijuana today and still test positive for marijuana a month later. This means that a person involved in a motor vehicle accident may test positive for marijuana but actually not be impaired in the slightest as they used marijuana several weeks ago, not recently.

The study also says that marijuana "contributed to" the accident. DUI and Criminal Defense Attorney Leonard Frieling says, "…'contributed to' means generally 'alcohol was present, and generally was the primary impairing substance.'" The studies authors never intended to imply that cannabis caused the accidents. In fact the authors of the study said, “The prevalence of non-alcohol drugs reported in this study should be interpreted as an indicator of drug use, not necessarily a measurement of drug impairment.” One of the study's authors, Guohua Li, elaborated on the point in a story in the Denver Post. “The most likely explanation is that use of marijuana in the general driver population has been increasing, which may reflect increased use in the overall population,” Li said.

What Li said is important because usage may be increasing, however, what is increasing is law enforcement testing for marijuana in traffic accidents. In the past they did not always test for marijuana thus some numbers could be skewed when comparing data to old numbers.

Before we proceed to the next point the previous two points are really measures of performance more than anything else. There is an iPhone app called Me Myself which is an app that is designed to measure performance and can assist you in tracking and monitoring your performance over time. Me Myself cannot tell you if you are able to perform certain tasks but it can help you track and measure your ability to perform before performing certain task. Are you on top of your game? Check out Me Myself for more information. (In full disclosure I am affiliated with Me Myself as a web developer as UBhapE2, however, I promote this app because I believe in its mission.)

3. It may harm the developing brain.

Although a causal connection has yet to be found, studies show regular marijuana use—once a week or more—can change the structure of the teenage brain. Marijuana affects memory and problem solving abilities, both of which can impact academic performance. Researchers from the Harvard School of Medicine and Northwestern University Feinberg School of Medicine surveyed a small group between the ages of 18 and 25 and noticed structural abnormalities in the brain, specifically in grey matter, the nucleus accumbens, and the amygdala, after recreational marijuana use.

Unless there is a valid medical reason marijuana should not be used by those underage. With that said Paul Armentano, NORML Deputy Director, summed up this point clearly:

"Using high–resolution MRI imaging, scientists identified specific changes in particular regions of the brain that they inferred were likely due to marijuana exposure. (Since researchers only performed a single MRI session, they could not say definitively whether these changes were, in fact, caused by cannabis or whether they existed prior to subjects’ use of the plant.) Notably, however, these changes did not appear to be associated with any overt adverse effects in subjects’ actual cognition or behavior. (Separate studies assessing youth use of legal intoxicants, such as nicotine and alcohol, have also been associated with documented changes in brain structure. Ditto for caffeine intake in preclinical models. These findings have received far less media attention.)

"Both the cases (20 marijuana users) and controls (20 nonusers) in the study were recruited from local universities, undermining the notion that the alleged ‘brain damaged potheads’ were any more academically challenged than their non-using peers. Further, as summarized by HealthDay: “Psychiatric interviews revealed that the pot smokers did not meet criteria for drug dependence. For example, marijuana use did not interfere with their studies, work or other activities, and they had not needed to increase the amount they used to get the same high.

"In other words, case subjects and controls appeared to function similarly in their professional and academic endeavors."

4. It could make you panic.

Marijuana may alleviate anxiety for some, but for others it can cause it. THC can cause increased heart rate, poor coordination, or lightheadedness, which can be triggers for anxiety attacks. Some research suggests that people who frequently use of marijuana—and who started using it as young adults—were more likely to have anxiety disorders or depression. Whether cannabis use causes anxiety disorders, however, is not known.

Marijuana is not for everyone. There are people who may have experienced bad reactions to marijuana. There are many marijuana strains and certain marijuana strains may be more prone to cause anxiety. This does not mean it is harmful to your health. They also reference research that frequent marijuana users are more likely to have anxiety disorders or depression. There has been research that contradicts this and that marijuana can decrease anxiety and depression.

In my personal experience I have never had a panic attack because of using marijuana and I have been using marijuana on an almost daily basis for several years. In fact, I use marijuana to treat anxiety from PTSD that developed in a highly abusive marriage. In speaking with people both in and out of Colorado most echo these feelings. Those that did have anxiety related to marijuana I spoke with said that their anxiety wasn't from the marijuana itself but from the fact they might get caught by police and sentenced to jail or prison.

Those who I have spoken with who have negative reactions to marijuana simply avoid using marijuana. Does this mean it was harmful to their health or others should not use it? Absolutely not.

5. It can be addictive.

One in 10 users exhibits symptoms of dependence, according to the American Psychological Association. Marijuana’s rate of dependence liability of 9% is comparable to that of anti-anxiety medications and is well under the liability rates of alcohol (15%) and tobacco (32%), according to a study by the Institute of Medicine. However, the reason why some become addicted and others don’t remains unclear. Genetic studies have suggested that the involvement, or lack thereof, of CB1 receptors in response to cannabis can influence the likelihood of addiction. The receptor gene has been found to have a connection to the development of dependence to drugs and alcohol. Studies done on animals suggest that cannabis triggers reward centers in the brain, including neurons that produce dopamine, which could also encourage continued use.

All substances on earth can cause dependence. I should note that dependence is not addiction. Addiction in its original definition is any strong habit. Dependence means your body relies on the substance. Dependence does not mean addiction and addiction does not mean dependence. Also Times is misusing the term "addiction" because research has shown that some people become dependent (not addicted) on any drug, not just cannabis, while others do not and the reasons remain unclear.

Animal studies can be misleading at times because many animal studies occur in confined environments and often the animals are traumatized by the procedure through which the drug is administered. Studies have shown that lab rats kept in comfortable, interesting environments are less likely to use drugs compared to the other studies.

We should note that dependence or addiction may not always be a bad thing. Anything can be used to excess and cause problem, however, a person who uses marijuana on a daily basis to treat pain may be dependent on the drug. You could also say they are addicted to marijuana because they use it daily; however, the person may have no negative effects from the use of marijuana. What studies should measure is when a person continues to do a behavior (drug related or otherwise) despite negative consequences of doing that behavior.

Also, it should be taken into consideration how the negative behavior is perceived. Let's take a person who uses medical marijuana and loses a job because of a drug test and the person doesn't stop using marijuana. While this is a negative consequence of marijuana use this negative consequence is directly caused by the prohibition of marijuana. Of course this assumes the person who uses marijuana comes to work unimpaired. If a person drinks on Friday night and goes to work on Monday, not drunk, they would be fine. The same should be for marijuana users because a person can get fired for a drug test despite the fact that they are completely sober while at work. The byproduct of marijuana can be detected for weeks after a single use.

6. It can stress your heart

Marijuana-related deaths are so rare as to be treated as mythological by marijuana boosters, but a paper published this spring in Forensic Science International does describe the deaths of two healthy men, ages 23 and 28, who experienced heart trouble after using marijuana. “To our knowledge, these are the first cases of suspected fatal cannabis intoxications where full postmortem investigations, including autopsy, toxicological, histological, immunohistochemical and genetical examinations, were carried out," the authors write. The authors surmise that the cardiovascular events were the result of increased heart rate that can happen in some pot smokers, particularly in the first hours after using marijuana. Nonetheless, the authors conclude, that the “absolute risk of cannabis-related cardiovascular effects can be considered to be low, as the baseline risk for most cannabis smokers is low and cannabis-induced changes are transient.”

This is misleading. Marijuana can increase your heart rate about as much as an espresso or exercise. For healthy individuals this has no harmful effects on your body. Marijuana strains also vary, there are many strains that one can smoke that will not increase your heart rate. For individuals with heart problems you may want to stay away from marijuana just as you would avoid exercise or drinks high in caffeine that could increase your heart rate. Also, many marijuana users will develop a tolerance to these effects and the effects will become less over time.

The information at the start of the point about the two young men that died is very misleading. The two young men both had heart defects they were born with and when they died they had detectable amounts of THC in their blood. This doesn't mean marijuana caused them to die. One of the two also had a history of past drug use (other than marijuana). Making the statement that marijuana killed them is a stretch. What killed them was their pre-existing heart condition. These two guys could have gone for a jog and fallen dead but do we say jogging killed them? No, we say their heart condition killed them. I could continue to elaborate about the way the media tried to twist this story but Dr. Mitch Earlywine explains this much better than I could on NORML's website.

As we can see, much of what the Times article says is harmful is either a temporary effect or blown out of proportion as being harmful. Should certain individuals avoid using marijuana? Yes. Should there be additional research into marijuana? Absolutely. But when looking at the overall picture marijuana has very few harmful effects if used responsibly.

This article was originally posted on Karmaceuticals website. Reprinted with permission.