At some point in your life, you or someone you know would have probably smoked marijuana. Don’t deny it. It’s a statistical fact that 1 in 3 people have used marijuana at some time. 1 in 10 people would have used it in the last 12 months. But what exactly is this popular drug (yes, it’s a drug)? Is it safe? What does it do to your body?
What is marijuana?
Marijuana is a form of cannabis that is derived from the cannabis plant (cannabis sativa). The main ingredient that provides the sensation of getting ‘high’ is called delta-9 tetrahydro-cannabinol, more commonly known as THC. Depending on the form of cannabis, there are varying intensities of feeling ‘high’.
There are three main forms of cannabis — the most popular of which is marijuana, followed by hashish and hash oil. Dried leaves and flowers of the cannabis plant is used as marijuana. Although it is the most popular of the 3 forms, it is the least potent and is commonly smoked like a cigarette (known as a ‘joint’) or in special waterpipes (bongs). We won’t go into detail about the equipment used. The focus of this article is the effects of marijuana.
Unlike other legal drugs i.e. alcohol and tobacco, marijuana is used to experience a sense of mild euphoria because it is a psychoactive drug. Users report mood changes (feeling happy) and changes in their perception of environment. If you’ve watched The 70’s Show, you’d have noticed that the walls move whenever one of them gets high. That’s an example of a change in perception.
The mechanism of action of marijuana and its active ingredient, THC, is pretty well-documented. Once you understand how THC takes over the body, you’ll also understand why one feels ‘high’ or ‘stoned’.
The normal human brain has certain receptors. These receptors are known as cannabinoid receptors or CB1. They are located all over the brain and are responsible for different brain functions. Physiologically, our body produces endogenous cannabinoids that interact with the appropriate receptors to result in normal brain function. The cannabinoids that we have in our bodies do not have any psychoactive effects so we go about our daily lives without feeling ‘high’.
CB1 receptors in a specific part of the brain are responsible for a specific chain of events that result in a specific action. For example, CB1 receptors in the cerebral cortex are partly responsible for sensory perception (that’s touch, sight, hearing, taste and smell).
CB1 receptors are also found in the:
- hippocampus — which is responsible for memory
- basal ganglia — which is responsible for emotion and initiating movement
- cerebellum — which is responsible for balance and coordination
When one smokes marijuana, THC is absorbed into the blood and is quickly delivered to the brain and interacts with the CB1 receptors all over the brain, interfering with their normal functions and providing us with distorted sensations.
Short term effects of marijuana use include a sense of euphoria (happiness), talkativeness, loss of inhibition, increased appetite, loss of coordination, bloodshot eyes, dryness of the mouth, increased heart rate, and decreased muscle strength.
Since THC is lipid-soluble, it is stored in fatty tissue and is slowly released for weeks or months.
Marijuana smoke contains carcinogens and a higher level of tar compared to cigarettes and users are at much greater risk of developing lung cancer. Marijuana also has negative effects on the reproductive system; reducing testicular size, lowering testosterone levels, decreasing libido, causing menstrual abnormalities, abnormal ova formation, impotence and changes in sperm shape and motility.
So before you light up again, think twice.
Disclaimer: I have no conflicts of interest. As with everything, you have to weigh the benefits and adverse effects of marijuana. The choice is yours.
References: CBRNE – Incapacitating Agents, Cannabinoids, Evidence that anandamide-signaling regulates human sperm functions required for fertilization., The toxicology of cannabis and cannabis prohibition, Pharmacology and effects of cannabis: a brief review, Psychiatric effects of cannabis, Cannabis use and progressive cortical thickness loss in areas rich in CB1 receptors during the first five years of schizophrenia, Identifying prenatal cannabis exposure and effects of concurrent tobacco exposure on neonatal growth.