Cannabinoids are compounds made by the Cannabis sativa plant. These compounds interact with our endocannabinoid system and can have medical benefits (1-3) or psychoactive effects (4-6).
However, C. sativa doesn’t just produce cannabinoids—it makes hundreds of different compounds! Two of the most famous groups of these compounds are cannabinoids and terpenes. While terpenes are mainly known for their smell, they can also affect our endocannabinoid system (7-10)
The Endocannabinoid System
Our endocannabinoid system is part of the human body, just like the digestive or cardiovascular systems. It helps control things like hunger, sleep, and pain (11-15). Our bodies even make their own cannabinoids, called endocannabinoids, such as anandamide.
But cannabinoids aren’t just made by humans. When they come from plants, they’re called phytocannabinoids. Some other plants produce cannabinoids too, but C. sativa makes a lot—and the most famous one is THCA.
THCA vs. THC
THCA stands for tetrahydrocannabinolic acid. The cannabis plant produces this compound in its acidic form. When we heat THCA, it turns into THC (tetrahydrocannabinol), which is its neutral form.
THC is psychoactive, meaning it changes how you think or feel. Because of this, many governments regulate it strictly. But there’s another famous cannabinoid: CBD.
Why does this matter? Because THC is the form that affects the brain the most. This is why people smoke, vape, or cook cannabis—to apply heat and turn THCA into THC.
What About CBD?
Like THCA, the plant also produces CBDA (cannabidiolic acid). When heated, it turns into CBD (cannabidiol).
But unlike THC, CBD is not psychoactive—it won’t make you feel “high”. However, it does affect the brain, so some called these effects psychotropic. Scientists are studying CBD for its medical potential (16-19), but there’s still a lot to learn about this and many other cannabis compounds.
Smoking, Vaping, Baking
As mentioned earlier, heating C. sativa flowers through smoking, vaping, or cooking turns THCA into THC through a process called decarboxylation. This process happens when cannabis is exposed to heat, transforming its cannabinoids into their most active forms, like THC and CBD.
What is Decarboxylation?
Decarboxylation is a chemical process that changes cannabinoids from their original form (acidic) into their active form (neutral). The neutral forms of cannabinoids have stronger effects on the body.
Decarboxylation can happen naturally over time, but heat speeds up the process [1]. The most common way to decarboxylate cannabis is by smoking it.
Why Does Cannabis Need to Be Decarboxylated?
Cannabis naturally produces cannabinoids in their acidic form, which includes an “A” in their names that stands for “acid”. For example:
- THCA (tetrahydrocannabinolic acid)
- CBDA (cannabidiolic acid)
These acidic cannabinoids don’t cause a “high” or have many medical benefits until they change into their neutral forms (like THC and CBD) through decarboxylation.
How Does Decarboxylation Happen?
Decarboxylation happens slowly over time, but heat speeds it up (20). The most common way to decarboxylate cannabis is smoking. When cannabis burns, the heat turns THCA into THC, which, as we mentioned above, is the form of the compound responsible for the “high.”
During this process, carbon dioxide (CO₂) is released, and cannabinoids lose some of their weight. For example, THCA loses about 12% of its mass when it turns into THC (21) and although different estimates (21-23) , the widely accepted industry conversion factor is 0.877 (24) This means that when THCA is decarboxylated into THC, its weight is reduced by a factor of 0.877. This occurs because the removal of the carboxyl group makes THC lighter than THCA, and the 0.877 factor is the standard used in the industry to account for this change.
Therefore, to estimate the total THC in a sample, we use this equation: Total THC = (0.877 × THCA) + THC. This formula helps measure how much THC will be available after heating because some of it starts as THCA, which needs to be converted.
The same happens when heating CBDA, which turns into CBD after decarboxylation.
What Happens to Cannabinoids After Decarboxylation?
Sometimes, cannabinoids go through other chemical changes after they’ve been decarboxylated. These changes don’t happen because of heat but because the compounds are exposed to air or light. One of these changes is oxidation, which can create new compounds.
CBN – Cannabinol
After THC is decarboxylated, it can break down further and turn into a different cannabinoid called CBN (cannabinol). This happens when THC is exposed to oxygen, causing it to lose hydrogen atoms and form more double bonds between carbon atoms.
CBN is known for its sedative (sleep-inducing) effects and is believed to be less psychoactive than THC.
Scientists have also found that CBD might turn into THC (delta-9-THC) or that THC can oxidize into CBN or delta-8-THC (a slightly different version of THC) before the cannabis is consumed [1].
Can CBD Turn into THC Inside the Body?
Now, here’s the big question: If you consume CBD, could it turn into THC inside your body and make you fail a drug test?
The short answer is no—this transformation only happens outside the body.
However, the tricky part is that many cannabis products contain multiple compounds. Even if CBD itself doesn’t turn into THC, some products may contain tiny amounts of THC. In some cases, these trace amounts could be enough to show up on a drug test, even if you only took CBD.
Legal Definitions
Some countries define hemp as C. sativa plants that make very little THCA but produce other cannabinoids like CBDA. These plants may not be the same as hemp grown for fiber or seeds—they’re actually more like marijuana plants. However, both hemp and marijuana are part of the same species, Cannabis sativa L.
In the United States, hemp is legally defined as any cannabis plant that produces less than 0.3% THC. Recently, the European Union also adopted this 0.3% THC limit.
For comparison, marijuana plants can contain up to 35% THC/A, though the average is 17-20% THC/A (25).
Why These Rules Are Tricky
It’s not always easy for plants to stay within legal THC limits. That’s because the enzymes (proteins) that create cannabinoids in the plant are messy and unpredictable (26, 27). But that’s a whole other story!
I hope this post has helped you better understand some of the cannabinoids produced by C. sativa and the process of decarboxylation. Stay tuned for more interesting facts in the future!
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