When Chemist Rafael Mechoulam first began his research on cannabis in the early 1960s, he found himself facing one major problem: where do you legally obtain cannabis for scientific study?

The answer? The police.*

Though hardly an appropriate supplier in today’s legal and political climate, the five kilos of hashish given to Mechoulam by Israeli police helped pave the way for some of the most groundbreaking findings in marijuana and biochemical research to date.

Mechoulam was the first man to isolate delta9-Tetrahydrocannabinol (THC), the primary psychoactive compound in cannabis.

What is delta9-Tetrahydrocannabinol?

THC is one of many chemical compounds known as cannabinoids found inside the resin glands primarily in the bud or flower of the female cannabis plant.

In organic chemistry, these cannabinoids act as secondary metabolites, or supplementary chemicals produced by the plant that don’t have a direct impact on plant development or reproduction.

Plants like marijuana produce these secondary metabolites in place of an internal immune system, fending off parasites, viruses, bacteria, and other natural predators. While THC itself does not have anti-bacterial properties in humans, other cannabinoids like cannabigerol (CBG) are known to kill or slow the growth of bacteria in people and plants alike.

The science behind THC

Tetrahydrocannabinol 1 What is THC?
THC Molecular Structure
Photo credit: “Tetrahydrocannabinol” by Yikrazuul – Own work. Licensed under Public Domain via Wikimedia Commons.

Out of the 85+ individual cannabinoids found in marijuana, only one of them produces an intoxicating, psychoactive effect: our good pal THC.

But why? The answer is simple: shape.

THC just happens to have the right molecular structure to fit into special binding sites on cells called neurotransmitters in very particular sections of your brain. These specific sections are now known to be parts of a larger, endocannabinoid system.

The endocannabinoid system: THC and the brain

Though THC was first isolated in 1964, it wasn’t until 1988 that Dr. Allyn Howlett of Wake Forest University uncovered the binding sites for THC in the human brain. What she discovered was nothing short of revolutionary: THC was attaching itself to special cell sites in the hippocampus (responsible for memory), the frontal cortex (where we think), and the cerebellum (responsible for movement).

These cell sites have been termed “cannabinoid receptors”, and each acts as a part of the larger endocannabinoid system.

As smoothly as keys fit into a lock, the binding of THC to a cannabinoid receptor spurs a chemical reaction, causing changes in your brain that directly impact behavior and cognitive ability.

Anandamide: Our natural THC

Some may ask: If THC fits so well into these receptors, then humans must be made to consume cannabis, right?

The short answer? No.

Once scientists managed to figure out how THC is used by the body via the endocannabinoid system, it took them another five years to isolate the THC-like substance that our bodies create naturally. That compound, what can very loosely be described as the human version of THC, is anandamide.

Modern scientists are still struggling to figure out exactly what complicated role anandamide plays in the human body, but one critical function sets this compound apart from all others.

Like nature’s own white-out, anandamide is a chemical that helps us forget. In a PBS documentary based on the bookThe Botany of Desire, author Michael Pollan explains:

It didn’t seem adaptive to me to have a drug for forgetting. Memory, we understand, has great survival utility […] But why would forgetting be adaptive? I asked Mechoulam this question, and he said: ‘Well, tell me, do you really want to remember all the faces you saw on the subway in the morning?’

Anandamide helps get rid of all of the clutter, allowing you to remember only the important things.

Understanding some of the essential functions of anandamide is immensely helpful to understanding the ways THC affects our bodies and sheds some light on the role of THC in treating certain psychological disorders, such as PTSD, where patients struggle to overcome the negative memories surrounding a traumatic event.

Decarboxylation: Light it up!

Okay, so we’ve learned that THC is the only psychoactive compound in cannabis, and we’ve learned that it takes the place of anandamide by binding to specific cell receptors in the brain. What else do we need to know about this miracle compound?

One word: decarboxylation.

You can’t just eat cannabis and expect to have a psychoactive experience. In its raw plant form, THC doesn’t actually exist in a shape that will trigger a psychoactive affect in humans.

Inside marijuana resin glands, or trichomes, THC is actually found as tetrahydrocannabinolic acid (THCa). In its acid form, it’s impossible for THCa to bind to cell receptors in our body because its simply the wrong shape. THCa has an additional carbon atom attached, and in order to fit into the proper cell receptors in our brain, you need to remove the acid group.

It may sound complicated, but really all you need is a little heat. When people smoke a joint, take a lighter to flower in a pipe, cook cannabis on a stovetop, or use something like a Magical Butter Machine, they are acting the part of an amateur chemist converting raw THCa into psychoactive THC.

Isn’t science fun?

Short Term Effects of THC

When smoking marijuana, you may experience the following side effects for up to 3 hours after inhaling:

  • Drowsiness
  • Dizziness
  • Redness in eyes
  • Dry mouth
  • Euphoria
  • Giggle fits
  • Increase in appetite
  • Increased heart rate
  • Skewed sense of time—typically time seems to slow down.
  • Reduced motor function

If ingesting cannabis via an edible, it may take anywhere between 30 minutes to two hours to fully feel the effects of THC. When the psychoactive effects begin to kick in, they will be much more potent than they are when consuming cannabis in a different form.

The immediate effects of THC will vary slightly depending on the individual cannabis strain due to factors like the total percentage of THC, and the percentage of other dominant cannabinoids present in that particular strain.

Your own body chemistry (such as your body’s ability to produce and process anandamide) will also significantly impact how you process and experience THC. For some, THC will help reduce anxiety and help create a sense of inner peace. For others, THC might have an opposite effect.

Long Term Effects of THC

Scientists are still debating the long term effects of THC, and thus far very little research has actually been found conclusive. Currently, short-term memory loss is just about the only side effect of habitual THC consumption that researchers have been able to consistently prove, though more research is needed to determine exactly how much and in what ways THC affects memory.

Some research claims that THC consumption is linked to increases in psychotic episodes in people at risk for schizophrenia, but this claim is highly debated as more nuanced research continues to be published.

How to Get Rid of THC in the Body

Typically, when employers or other institutions test for THC in your system, they rely on urine tests that look forTHC metabolite THC-COOH. How long this metabolite stays in your system depends entirely on how often you consume THC and your body’s individual metabolism; the more you consume, the longer it will take before it’s completely eliminated.

Generally, for occasional to light consumers, THC-COOH will be out of your system in 3-14 days. For extremely heavy consumers, it’s not uncommon to test positive 30 to 60+ days after the fact.

The best way to flush THC-COOH from your system before a urine test is simply to drink water. Drinking water dilutes your urine, lowering the total number of nano grams per milliliter. Drinking too much water, however, may spoil the sample.

Unfortunately, your body stores excess THC in fat cells, meaning that for regular consumers, it’s nearly impossible to completely eliminate all of the THC in your system in one sweep.

A piece of advice: avoid hitting the gym before taking a urine test.


Cannabidiol What is THC?
CBD Molecule.
Photo credit: “Cannabidiol” by Harbin – Own work. Licensed under Public Domain via Wikimedia Commons.


As previously explained, THC is the only psychoactive compound in marijuana. So what’s with all the talk aboutcannabidiol, or CBD?

CBD is the second most prevalent cannabinoid in marijuana, but unlike THC, it doesn’t bind to specific cannabinoid receptors in the body and is non-psychoactive.

CBD works its magic by inhibiting the enzyme fatty acid amide hydroxyls (FAAH), which is the enzyme that destroys anandamide in the body. This increases the amount of anandamide present in your system, since enzyme FAAH can no longer destroy it.

CBD also has been shown to mute the psychoactive effects of THC, though as with most marijuana science, more research is needed to understand exactly how these two substances interact with one another.

Medicinal Value of THC

As marijuana continues to gain acceptance in mainstream culture, more and more studies are coming out that bring the medical value of THC to light. Most remarkable are the findings on THC as a potential treatment for cancer.

Researchers at the Compultense University of Madrid have found that THC actually causes tumor cells to auto-digest themselves in animal models, meaning that THC may play a vital role in drastically reducing tumor size and prevalence.

THC has also been used in mainstream pharmaceutical companies to produce drugs like Marinol, a prescription medication that increases appetite and reduces nausea in cancer patients.

Each year, more research points to the efficacy of THC as medicine. Thus far, THC is thought to lend a helping hand in treating the following conditions:

  • Alzheimer’s Disease
  • Atherosclerosis
  • Stroke
  • Glaucoma
  • Neuropathic pain
  • Multiple sclerosis
  • Parkinson’s Disease
  • Sleep apnea
  • ADHD
  • Tourette syndrome
  • PTSD
  • Cancer (various forms)

THC-Based Recipes

In case all of this talk about THC has given you a healthy appetite for marijuana, take a look at some of these great THC infused recipes:

When it comes to THC, the research summarized in this article is only the tip of the iceberg. Through studying THC thus far, scientists like Rafael Mechoulam and Allyn Howlett opened our eyes to a complex biochemical system that we are only just beginning to understand.

Though THC has shown tremendous potential as a medicine and as a tool helping us to understand the intricate ways our internal chemistry influences our psychology, legal and political roadblocks still prevent us from diving in and fully examining what the cannabis plant can teach us about ourselves.

Help us elevate the conversation around the cannabis plant and THC by sharing this article and educating others on the cannabis movement. We encourage you to engage in discussion by sharing your thoughts and ideas — we’d love to know what you think!

* Mechoulam acquired cannabis from Israeli police once when he first began his cannabis research. After that, he used proper procedure and acquired cannabis legally through a rigorous application process determined by the Israeli government.

Header photo credit: Wikipedia

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