The Effects of Cannabis (Marijuana) on the Brain & Body

Smoking marijuana chronically, meaning more than twice a week, does appear to reduce testosterone significantly and elevate so-called aromatase enzymes, which are the enzymes that convert testosterone into estrogen.

So, when prolactin levels are up, dopamine levels are down. Smoking marijuana more than twice a week significantly increases prolactin. There are fewer studies exploring whether or not edible marijuana has the same effect, although the preliminary evidence suggests that it does not.

Whether or not you smoke or vape tobacco or cannabis, you are severely impairing the function of endothelial cells that make up the capillaries and blood vessels of your brain and body. And that is known to decrease cognitive capacity over time, increase probability of strokes, severely impact lung function...

The process of smoking, of inhaling smoke into the lungs, and yes, also vaping... are both severely detrimental to endothelial cells ... Now, we can see a huge number of negative health effects of vaping, some of which are distinct from the effects of smoking.

There are very strong data... pointing to the fact that for people who are chronic users of cannabis—that is using it twice a week or more—that, over time, their levels of anxiety actually increase.

Cannabis use itself makes people four times likelier to develop a chronic major depression.

If someone experiences paranoia or anxiety from a given strain of the marijuana plant or from ingesting an edible in a particular way or particular kind of edible, that person is very likely to experience the same effect every time they ingest that strain or variety.

THC, in particular... is known to be strongly inhibitory for something called gonadotropin-releasing hormone ... Reduced levels of gonadotropin-releasing hormone caused by cannabis use reduce levels of LH (luteinizing hormone) & FSH, which reduce levels of testosterone & sperm production in males and egg health & ovulation & menstrual function in females.

To be very clear, cannabis use between the ages of 16 to 24 in both males and females, is increasing anxiety, increasing depression, in the immediate years ... In addition to that, the cannabis use, and because of the signaling mechanisms involved, are predisposing those individuals to psychosis later in life.

People who are more open to experience are more likely to use cannabis, and people who use cannabis are going to be more open to new experiences. And that combination of features, openness to experience and what that openness to new experiences brings, enhances the convergent and divergent thinking that is characteristic of the creative process.

Does cannabis increase sexual arousal? Well, it depends. If you fall into the category of person who has elevated levels of prolactin in response to cannabis, then no, actually, cannabis will suppress your sexual response and desire. If, however, you are in the category of person that does not have elevated levels of prolactin in response to cannabis, then erotic stimuli can potentially, and in fact, do increase sexual arousal in the majority of individuals.

There is a vast literature on the effects of cannabis on fertility ... It does seem to alter sperm motility and sperm health & function, when taken chronically more than twice per week.

The most recent survey of pregnant mothers in the United States show that 15%... of pregnant mothers report using cannabis in some form or another.

It's very clear that depression increases over time... especially for individuals that were not depressed at the outset of their use. In other words, they didn't start using cannabis because they were depressed, but rather, the depression starts to emerge as a consequence of the cannabis and THC use.

THC and CBD, when they're brought into the brain and body... they bind to those receptors, those endogenous cannabinoid receptors, and they tap into the same systems that your endogenous cannabinoids would tap into—the ones that affect mood and energy and creativity and relaxation, etc.—but they do so with thousand-fold greater potency...

[Indica strains] also tend to shut down the hippocampus, an area of the brain associated with memory, which is why indica varieties lead to pronounced, or I should say profound, defects in short-term memory and sometimes in long-term memory as well if it's consumed over long periods of time.

Cannabis users, even if they are not under the influence of cannabis, are far more open to novel ideas, and they have a more explorative and reduced anxiety, or I should say lower anxiety, mode of thinking when they explore novel ideas, which is essential for divergent thinking.

If you look at individuals who start using cannabis even younger—age 14, or even as young as 12—the probability of psychosis later in life, in particular schizophrenic or schizophrenic-like episodes, more than doubles.

The more often young people, meaning individuals between the ages of 14 and 25, the more often they consume or smoke or vape cannabis, the faster and the more extreme that cortical thinning is. And that cortical thinning is occurring in exactly the area of the brain that's involved in planning, in control over one's emotions, in reflexes, in organizing one's life...

Chronic cannabis use (more than twice per week) has consistently been associated with mental health disorders ... Heavy cannabis use, meaning cannabis use more frequent than twice per week, has been associated with four times the risk of psychosis later in life—in particular, schizophrenia and bipolar-like episodes.

THC and CBD and the other components of cannabis bind to those receptors, those endogenous cannabinoids receptors... with much greater affinity and exert a vastly greater potency and effect on mood and perception, etc. than do our endogenous cannabinoids.

If you evaluate the potency, that is, in technical terms, that would be affinity with which these compounds (THC and CBD and CBN) bind to these endogenous receptors, that would be like a Howitzer gun, like a cannon, going off as compared to endogenous cannabinoids, whether or not it's AEA or to 2-AG, which is more like a cap gun level of activation, at least in this analogy.

Cannabis is very fast to enter the bloodstream. In fact, within 30 seconds, it's going to enter the brain and permeate throughout the brain and body.

When dopamine levels are high, divergent thinking is more likely. That is, when people have a lot of dopamine circulating in their system, they tend to be very expansive with their ideas. They tend to brainstorm a lot. They tend to be comfortable and even want to or reflexively throw out a lot of ideas that sometimes even seem a little disconnected.

When dopamine levels are high, convergent thinking is not very likely; and when dopamine levels are low, convergent thinking is very likely.

Some people's prolactin levels go up when they ingest cannabis, and those people do not achieve elevated levels of sexual arousal when under the influence of cannabis if they're looking at erotic stimuli.

The more potent the THC concentration, the higher probability of developing psychosis or a major depressive episode or a major anxiety disorder later in life.

The sativa varieties tend to make people feel a little bit less susceptible to pain and noxious stimuli, which are basically stimuli that you don't like. So, the sativa varieties are often prescribed or are used in the recreational context for pain management and relief.

If we were to look at the three most commonly used drugs, alcohol will be at the top of the list ... Many billions of people also use nicotine; it's the second most consumed drug ... And then the third most consumed drug is cannabis in one form or another.

If one ingests CBD or THC, smokes cannabis, ingests orally, doesn't matter, it's going to stay in that fatty tissue and can be detected for at least as long as 80 days after ingestion.

The typical age of initiating cannabis use nowadays is about 19-years-old ... About 20% of people in that age bracket of 16 to 24-years-old are using cannabis daily, either by vaping by smoking or by edible.