*Note: This article is part of a larger report featured on Wondergressive entitled ‘Cannabis Cures Cancer and Everything Else: A Through History and Review‘
Copyright © 2013 [Eric Feinberg]. All Rights Reserved.
What the Critics Have to Say About Cannabis
(And Why They’re Wrong…)
Critics are quick to point out the consistently noted dangers of cannabis ingestion. These are the same arguments that have been used for decades. They remain aggressively debated without compromise, despite decades of rational evidence suggesting falsity and fallacy. The seemingly valid concerns regarding cannabis use that top the critics’ list are: the gateway drug theory, short-term memory loss, psychosis, decreased intelligence, harm from cannabis smoke, depression, an elevated heart rate, and worries over driving while high. Let’s allow science and logic to save the day, shall we?
Many critics of cannabis use claim that cannabis is a gateway to harder and more persistent drug use. They are implying that if a person uses cannabis, recreationally or medically, they are more likely to use dangerous drugs like cocaine (again, ironically listed as a schedule 2 drug) or heroin. Although multiple studies have found that cannabis users are more likely than non-users to engage in the use of more ‘hardcore’ substances (meaning higher addiction potential and/or more biologically detrimental), there are endless holes in this argument.
Related Article: The Incredibly Diverse Medicinal Properties of Cannabis
First, let’s start with the fact that there is no definitive evidence that cannabis use is responsible for the ingestion of harmful drugs. According to former US Surgeon General Dr. Joycelyn Elders:
Much of their [US drug-policy leaders] rhetoric about marijuana being a ‘gateway drug’ is simply wrong. After decades of looking, scientists still have no evidence that marijuana causes people to use harder drugs. If there is any true ‘gateway drug,’ it’s tobacco.
Alcohol and tobacco are more accessible and far more likely to be used by teens, consequently making those substances more likely to lead to further drug use. As stated by Elders, they are the true gateway drugs. In one of the most highly credible and sourced assessments on the science of drug use, the Institute of Medicine stated that:
In fact, most drug users do not begin their drug use with marijuana–they begin with alcohol and nicotine, usually when they are too young to do so legally…
There is no evidence that marijuana serves as a stepping stone on the basis of its particular physiological effect.
Starting to see the trend here? Alcohol and tobacco are far more dangerous and addictive than cannabis. If the gateway drug theory did have any legitimacy, it would have to be applied to alcohol and nicotine, two completely legal substances, before it could be attributed to any other substance.
Related Article: The History and Legality of Cannabis Use Around the World
The best analogy I’ve ever encountered for the ridiculousness of the gateway drug theory comes from Lynn Zimmer, PhD, Professor Emeritus at Queens College at the City University of New York:
In the end, the gateway theory is not a theory at all. It is a description of the typical sequence in which multiple-drug users initiate the use of high-prevalence and low-prevalence drugs.
A similar statistical relationship exists between other kinds of common and uncommon related activities. For example, most people who ride a motorcycle (a fairly rare activity) have ridden a bicycle (a fairly common activity). Indeed, the prevalence of motorcycle riding among people who have never ridden a bicycle is probably extremely low. However, bicycle riding does not cause motorcycle riding, and increases in the former will not lead automatically to increases in the latter.
Nor will increases in marijuana use lead automatically to increases in the use of cocaine or heroin.
Not surprisingly, a study of 4,000 participants suggests that cannabis use discourages the use of harder drugs. Another study suggests that any trace of the gateway effect disappears by age 21. What is more likely to lead to additional drug use is not cannabis itself, but the overly harsh penalties of cannabis use. Karen Van Gundy, who is a sociologist at the University of New Hampshire, did not set out to disprove the gateway theory, but nevertheless found that, rather than cannabis itself:
If we overly criminalize behaviors like marijuana use among teens, this could interfere with opportunities for education and employment later on, which, in turn, could be creating more drug use.
The gateway drug theory is weak and unfounded. It is in fact not a credible theory at all. It has no place in the realm of science.
It is a propaganda technique that we have been hearing for nearly the entire 20th century and it continues into the 21st century; cannabis makes you stupid, a loser, a burnout.
While there is clear evidence that cannabis, like other substances, alters perception and brain function, there is no evidence that cannabis alters brain function in a purely negative way. Additionally, there is absolutely zero evidence that the biological effects of cannabis are permanent. On the contrary, science tells us that all of the consistently noted negative biological aspects of cannabis are entirely temporary.
Related Article: The Power of Hemp Seeds: Behold Powerful Nutrition
According to Igor Grant, MD, Executive Vice Chairman at the University of California, San Diego Department of Psychiatry:
Smoking marijuana will certainly affect perception, but it does not cause permanent brain damage. ’The findings were kind of a surprise. One might have expected to see more impairment of higher mental function. Other illegal drugs, or even alcohol, can cause brain damage…
If we barely find this tiny effect in long-term heavy users of cannabis, then we are unlikely to see deleterious side effects in indivduals who receive cannabis for a short time in a medical setting…
If it turned out that new studies find that cannabis is helpful in treating some medical conditions, this enables us to see a marginal level of safety.
Dale Gieringer, PhD, State Coordinator of CalNORML explains that the notion that cannabis decreases intelligence is based entirely on a study that was later proven to be inaccurate:
Government experts now admit that pot doesn’t kill brain cells.
This myth came from a handful of animal experiments in which structural changes (not actual cell death, as is often alleged) were observed in brain cells of animals exposed to high doses of pot. Many critics still cite the notorious monkey studies of Dr. Robert G. Heath, which purported to find brain damage in three monkeys that had been heavily dosed with cannabis. This work was never replicated and has since been discredited by a pair of better controlled, much larger monkey studies, one by Dr. William Slikker of the National Center for Toxicological Research [William Slikker et al., 'Chronic Marijuana Smoke Exposure in the Rhesus Monkey,' Fundamental and Applied Toxicology 17: 321-32 (1991)] and the other by Charles Rebert and Gordon Pryor of SRI International [Charles Rebert & Gordon Pryor - 'Chronic Inhalation of Marijuana Smoke and Brain Electrophysiology of Rhesus Monkeys,'International Journal of Psychophysiology V 14, p.144, 1993].
Neither found any evidence of physical alteration in the brains of monkeys exposed to daily doses of pot for up to a year.
The surprising truth is that cannabis actually promotes the creation of new neurons in hippocampal regions of the brain, the part of the brain most responsible for memory. Xia Zhang, an expert at the Neuropsychiatry Research Unit, Department of Psychiatry, at the University of Saskatchewan in Canada along with other medical researchers, points out that cannabis is the only illicit drug ever found to promote the creation of brain cells:
We show that 1 month after chronic HU210 [high-potency cannabinoid] treatment, rats display increased newborn neurons [brain cell growth] in the hippocampal dentate gyrus [a portion of the brain] and significantly reduced measures of anxiety- and depression-like behavior.Thus, cannabinoids appear to be the only illicit drug whose capacity to produce increased hippocampal newborn neurons is positively correlated with its anxiolytic- [anxiety reducing] and antidepressant-like effects.
Multiple long-term studies have found that there is no significant difference in cognitive decline between heavy users, light users, and nonusers of cannabis. Intelligence, or a lack thereof, depends on a great deal of variables, including genetic makeup, nutritional status, health status, formal education, and age-related developmental processes, but cannabis use is not one of them.
Related Article: Cannabis Protects Brain From Damage While Binge Drinking
From a social standpoint, studies have even found that kids who use cannabis and other illicit substances usually have a higher IQ than their peers. Additional studies found that:
College students who smoke cannabis demonstrate comparable or even higher grades than their cannabis abstinent classmates, and are more likely to pursue a graduate degree.
The short answer is yes, cannabis alters your mind and body, like any other substance in the world, but it does not make you stupid (certainly you’re not going to claim any of these highly successful cannabis-users are stupid), and all of the physiological and psychological effects are temporary.
Critics of cannabis use argue that memory loss, especially short-term memory loss, occurs more prominently in cannabis smokers. They also claim that it is a permanent effect. All of these claims are either exaggerated or wrong. We’ve already discussed how all the effects of cannabis ingestion are completely temporary; the same applies to memory.
To begin, it is true that cannabis has a noticeable effect on short-term memory as well as working memory, while the user is under the influence. Cannabis affects working memory through the mechanisms stated above, by encouraging neurogensis, or the creation of neurons, in the hippocampus region of the brain. Although this has a positive effect on memory overall, it disrupts short-term memory while the user is ‘high’ by creating ‘noise’ in the hippocampus. These effects are detectable at least 7 days after heavy cannabis use,
but appear reversible and related to recent cannabis exposure rather than irreversible and related to cumulative lifetime use.
Furthermore, after extensively studying cannabis use, lead researcher and Harvard professor Harrison Pope came to the conclusion that:
From neuropsychological tests chronic cannabis users showed difficulties, with verbal memory in particular, for ‘at least a week or two’ after they stopped smoking. Within 28 days, memory problems vanished and the subjects ‘were no longer distinguishable from the comparison group.’
These tests affirm that the physio/psychological effects of cannabis are temporary and reversible.
Related Article: Federal Judge Urges Decriminalization of Marijuana
As for the seriousness of the temporary effects on short-term memory, studies have found that the effect is negligible. Researchers from the University of California, San Diego School of Medicine headed by Dr. Igor Grant analyzed data from 15 previously published controlled studies involving 704 long-term cannabis users and 484 nonusers and found that:
long-term cannabis use [is] only marginally harmful on the memory and learning. Other functions such as reaction time, attention, language, reasoning ability, perceptual and motor skills [are] unaffected. The observed effects on memory and learning, [show] long-term cannabis use [causes] ‘selective memory defects’, but that the impact [is] ‘of a very small magnitude.’
In fact, rather than having deleterious effects on memory, Ohio State University scientists have shown that
specific elements of marijuana can be good for the aging brain by reducing inflammation there and possibly even stimulating the formation of new brain cells.
Research supports this claim as past studies have revealed that cannabinoid receptors stimulated by cannabinoids in cannabis act as an anti-inflammatory agent and serve to improve memory in old rats.
Surprisingly, recent research into the activity of the hippocampus suggests that the key to a good memory is forgetting. Think of the brain as a computer with enormous hard drive space. Despite this incredible amount of storage, it is still finite. The more memories our brains create, the harder it is for our working memory to properly remember and recall. In this way, forgetting a few things actually isn’t a bad thing. It is in fact highly beneficial overall.
Another important point is that different cannabinoids found in cannabis affect memory centers in the brain in remarkably different ways. Through further legalization, scientists will have the freedom to perform more extensive research, while growers will have the opportunity to create strains of cannabis that have an even more minimal effect on the memory centers of the brain.
These studies reveal that in the short run, short-term and working memory are disrupted by the ingestion of cannabis by creating new neurons in the memory centers of the brain. These additional neurons disrupt working memory by acting as additional ‘noise’ to the active, recalling mind. These short-term memory lapses are completely temporary though, and in the long run the brain is actually left with additional neurons and a more expansive memory center. To use the analogy of a computer again, think of heavy-cannabis ingestion as a temporary lapse in primary memory functionality for the sake of upgrading the storage capabilities of secondary memory.
Elevated Heart Rate
It is true that many cannabis users describe symptoms of panic and consequently an elevated heart rate, especially during their first time trying cannabis. What still remains debated is whether cannabis itself biologically causes heart rate to increase.
The most well known study done on the correlation between cannabis and heart rate, and subsequently the only truly credible and widely used study, is one performed by a man named Dr. Murray A. Mittleman. Mittleman’s study focused on:
information on cannabis use from 3,882 middle-aged and elderly patients who had suffered heart attacks. A total of 124 patients were identified as current users, including 37 who reported smoking the drug up to 24 hours before their attack, and nine who had used it within an hour of experiencing symptoms.
Mittleman’s conclusion was that the first hour after taking cannabis heart attack risk is 4.8 times higher than during periods of non-use. In the second hour, the risk drops to 1.7 times higher. According to Mittleman this was the first study to document that smoking cannabis could trigger a heart attack, but that the trigger mechanism remained unknown. So what’s the issue with this constantly cited study?
Besides the fact that any type of smoke entering the lungs produces the same effect (it is not necessary and not medicinally optimal to smoke cannabis, a subject that is covered later in this report), Dr. Lester Grinspoon, who is one of the world’s foremost cannabis researchers as well as Associate Professor Emeritus of Psychiatry at Harvard Medical School and a former senior psychiatrist at the Massachusetts Mental Health Center in Boston for 40 years, explains why this study should be dismissed. Dr. Grinspoon tells an interviewer, in response to Mittleman’s study:
..let me say that since 1967 there have been numerous reports and studies, each of which the American media has blown out of all proportion, stating one or another supposed ill effect of marijuana use. I can list them, if you’d like. ‘Increase in the size of the ventricles, decrease in testosterone, destruction of chromosomes.’ All were front-page stories, none of them have ever been replicated. In other words, they didn’t pan out scientifically. Of course, the studies that contradicted them ended up on page 31 or thereabouts, if they got mentioned at all… I would point out that out of 3,882 patients, we’re talking about 9 who used marijuana within an hour of the onset of a heart attack. That’s around 0.2%. By sheer mathematics, given that people sleep eight hours per day or so, we can deduce that 6.7% of those patients emptied their bowels within an hour of onset. It’s incredible to me that the numbers here could be said to constitute a significant risk factor.
So, as is typical of the main stream media, a report was utterly sensationalized and relatively negligible data was heralded as proven truth. Dr. Grinspoon elaborates on the shortcomings of the study by reminding the interviewer that:
[Mittleman] put that increase [in heart rate] at 40 beats per minute. In truth, that number is closer to 20 beats per minute, which is probably consistent with running up the stairs in one’s house...I blame the media far more than I do Dr. Middleman. I read his abstract, and in its conclusion he cautioned against making too much of the data…in 1997, Kaiser Permanente did a large-scale study which included more than 65,000 admitted marijuana users, and they could not demonstrate any impact of marijuana use on mortality. If marijuana use really was a significant risk factor for heart attack, it is hard to believe that it didn’t turn up there. Again, I’m not saying that there is absolutely no risk demonstrated here. But given the history of the research since 1967, I’d be surprised if these findings don’t go down the same chute as all of the other front-page scare stories.
It’s really not that hard to believe. We have seen the same baseless scare tactics take place 20 years ago, 40 years ago, 60 years ago, 100 years, and more!
Related Article: Uruguay to Legalize Marijuana
With regards to actual significant scientific data, cannabis has in fact been shown (as stated in the ‘Cannabis Cures Everything’ section of this report) to treat and protect the heart, as well as help prevent heart disease through the interaction with the endocannabinoid system of the heart and surrounding regions of the body. It is consequently a likely tool for fighting and preventing obesity (along with hemp seeds). The science is still emerging, but what little research exists strongly suggests that cannabis will serve an extremely positive role in keeping the heart healthy in the future.
The single study that is consistently used to argue that cannabis poses a danger to cardiovascular health is far from significant and only became prominent through sensationalized media. Repeat studies suggest the cannabinoids found in cannabis play a pivotal role in cardiovascular health and the prevention of heart disease.
*Note: This article is part of a larger report featured on Wondergressive entitled ‘Cannabis Cures Cancer and Everything Else: A Through History and Review‘
Elevated Heart Rate