what is thca in weed

THCA and THC: What’s the difference?

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  1. Why we get high on THC and not THCA, how cannabinoids convert, and raw cannabis as a superfood
  2. THCA vs. THC: decarboxylation process

Why we get high on THC and not THCA, how cannabinoids convert, and raw cannabis as a superfood

Surprise! You’re just not going to get high by eating that freshly picked weed. At all. When cannabis is harvested and raw, no matter how much potential resides within, there is practically none of marijuana’s most famous and intoxicating cannabinoid, delta-9-tetrahydrocannabinol (THC). There is, however, a wealth of tetrahydrocannabinolic acid (THCA), an inactive compound found within the trichomes of living cannabis plants.

So, if someone ever asks you “ what does THC stand for?” don’t confuse the two similar terms. As you’ll soon discover, they are vastly different in both chemical structure and how they interact with the human body.

THCA is a cannabinoid that until recently has been closely compared to THC. Though THCA doesn’t get one high and THC certainly does, there is a relation: THCA is the precursor to psychoactive THC effects .

So why does THC get us elevated and THCA doesn’t? The reason is due to the three-dimensional shape of the THCA molecule. It is a larger molecule that doesn’t fit into our cannabinoid receptors, specifically the CB1 receptors. A cannabinoid must fit into a body’s CB1 receptor in order to have an intoxicating effect at all.

The cannabis plant produces hundreds of cannabinoids , the chemical compounds responsible for the therapeutic and psychoactive effects of cannabis. Only a few cannabinoids contribute to the euphoric high that is unique to the cannabis plant, though. The most celebrated, researched, and sought-after is THC.

It’s commonly assumed that as a marijuana plant grows, it is ramping up THC levels until ripe for the picking. But the primary cannabinoid being produced is actually THCA. How does THCA become THC?

The simplified answer is through heat and light — or the process of decarboxylation . Heat removes a carboxylic acid group of atoms from THCA, converting it into a molecule and altering the THC chemical structure , thus becoming the perfect shape to fit into our endocannabinoid system (ECS) and the CB1 receptors that run throughout the central nervous system, producing that classic elevated experience.

In a process called decarboxylation, heat removes a carboxylic acid group of atoms from THCA, converting it into a molecule and altering the THC chemical structure.

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The non-intoxicating effects of THCA are a big part of the reason that fresh, raw, unheated cannabis is a superfood. You may have heard of juicing cannabis or adding raw cannabis to smoothies for health enhancement. There’s good reason for that.

Like other superfoods, including avocados, kale, Greek yogurt, green tea, and garlic, raw cannabis has the potential to ease arthritis, chronic pain, fibromyalgia, and other ailments.

THCA is believed to offer an assortment of medicinal benefits and is commonly used as a nutritional supplement and dietary enhancement for its:

  • Anti-inflammatory properties – A 2011 study published in the Biological and Pharmaceutical Bulletin suggested that, along with other cannabinoids, THCA demonstrated anti-inflammatory properties.
  • Anti-proliferativeproperties – A 2013 study that analyzed cell cultures and animal models concluded that THCA could prevent the spread of prostate cancer cells.
  • Neuroprotective properties – In a 2012 preclinical study published in Phytomedicine, researchers found that THCA showed the ability to help protect against neurodegenerative diseases.
  • Antiemetic properties (increasing appetite and decreasing nausea) – A 2013 study conducted by researchers at the University of Guelph in Ontario found that both THCA and CBDA were effective in reducing nausea and vomiting in rat models, even more so than THC and CBD, respectively.

Most cannabinoids, including cannabidiol ( CBD ), cannabigerol (CBG), and tetrahydrocannabivarin ( THCV ), are in the acidic form (CBDA, CBGA , and THCVA) when cannabis is harvested. The unactivated forms of THC and CBD , along with other cannabinoids, have benefits themselves that we are still learning about.

It’s only after these unactivated cannabinoid acids go through the decarboxylation process, though, that they become the cannabinoids we’re most familiar with and that most interact with our ECS.

The acidic precursors are considered “thermally unstable,” which is another way to emphasize that they will alter when exposed to heat. Because of this instability, the molecules lend themselves to several different methods of decarboxylation.

THCA vs. THC: decarboxylation process

Here are the most common ways that weed is decarboxylated:

Sunlight conversion: THCA converts to THC in varying degrees through exposure to heat or light. If a cannabis plant sits in the warm sun for an extended period of time, its THCA molecules will slowly convert to THC.

Room temperature conversion: THCA also converts to THC when stored at room temperature for a long enough time. In olive oil, 22% of THCA will convert over the course of 10 days at 77 degrees Fahrenheit, or 25 degrees Celsius. Under the same conditions, 67% will convert in an ethanol extraction. And over time, cannabis stored at room temperature and with little light exposure, will convert 20% of its THCA into THC.

Smoking: When a flame is used to smoke dried, cured bud, a high degree of heat is applied in a short amount of time, resulting in the rapid conversion of THCA to THC. However, not all THCA will convert and, though smoking is the most common way to enjoy THC’s effects, it’s not the most efficient.

When a flame is used to smoke dried, cured bud, a high degree of heat is applied in a short amount of time, resulting in the rapid conversion of THCA to THC. Photo by: Gina Coleman/Weedmaps

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Vaporizing: This is perhaps the most efficient way of decarboxylating ground nugs. When heated at a low temperature, the cannabinoids are converted and released. Continuing to increase the heat will make sure that the prime amount of THCA is converted into THC and binds to CB1 receptors.

Vape pens: Even more efficient than vaporizing flowers is the use of already decarboxylated cannabis distillate found in preloaded vape pens. Since the THCA is already mostly converted to THC and the following vaporization takes care of even more, this is a good, efficient method of taking in intoxicating cannabis. Be sure you’re using a reliable brand of vape pen, for safety’s sake , and do your best to purchase products that are recyclable.

Cannabis concentrates: By isolating the THCA content from a cannabis plant, THCA crystalline can be extracted and consumed in dabs. Similar to vaporization, decarboxylation transpires rapidly when using the dabbing method, breaking down the THCA into active THC. In its pure form, THCA crystalline has little flavor or aroma, as most cannabis extractions aim to strip away the terpenes and flavonoids to isolate the cannabinoids. But many producers reintroduce cannabis-derived terpene blends back into the concentrate. Not only does the addition of terpenes improve the flavor, but these distinctively aromatic plant molecules also work together with cannabinoids to produce entourage effects that enhance the therapeutic potential of cannabis.

Conventional oven: When making edibles, you’ll want to activate, or decarboxylate, the weed before adding it to the butter, oil, or other medium. When weed gets ground up, spread evenly across a baking sheet that’s lined with parchment paper, and is baked at 230 degrees Fahrenheit, or 110 degrees Celsius, for 30-90 minutes (depending on the bud’s moisture content), it slowly converts most THCA into THC.

When making edibles, you’ll want to activate, or decarboxylate, the weed before adding it to the butter, oil, or other medium. Photo by: Gina Coleman/Weedmaps

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Whether cannabis is smoked, eaten, vaped, or juiced raw, understanding the plant’s properties and how and why they interact with our bodies the way they do is crucial in achieving the desired effects and avoiding adverse side effects . Cannabis molecules each have their own benefits and as raw cannabis is further studied, we can rest easy knowing that it’s safe to integrate it into a healthful diet.

There is a big difference between THCA & THC. Learn the differences between the two and how that affects your body.

THCA and THC: What’s the Difference?

What if we told you there’s almost no THC in your cannabis plants? You might not be too pleased! But don’t worry, the potential is there. Raw cannabis isn’t psychoactive in and of itself. It contains high levels of THCA, which only converts into THC via heat and light. Both of these cannabinoids are unique; read on to find out how they compare.

THCA & THC: Questions & Answers

The cannabis plant produces a vast range of interesting phytochemicals. The small crystalline structures on the surface of buds, known as trichomes, work hard to synthesise over 100 cannabinoids and over 200 terpenes. While the latter are found all throughout nature, many cannabinoids are unique to Cannabis sativa.

Before being exposed to heat, cannabinoids such as THC exist as cannabinoid acids—precursors that occupy the raw flowers. Although not as well-known, cannabis scientists are currently studying these “underdogs” for their effects.

THCA, or tetrahydrocannabinolic acid, serves as the biosynthetic precursor to THC. All high-THC strains feature high concentrations of this molecule before undergoing decarboxylation (heating). Continue reading to find out everything you need to know about this molecule.

What Is THCA?

What’s your favourite strain? Maybe you adore the tantalising tastes of Sweet ZZ, or the sheer intensity of Green Gelato. Whatever your favourite high-THC strain is, they’re all loaded with THCA until the second you light them up.

Despite what popular culture and bombastic news stories state, eating a pile of raw cannabis simply won’t get you high. Cannabis only becomes psychoactive after being exposed to heat, light, or ageing. Before these factors take hold, all of that THC exists as THCA.

Like many other cannabinoids, THC starts off life as CBGA (cannabigerolic acid), otherwise known as the “mother” cannabinoid. Cannabis plants also produce a set of enzymes that convert this precursor into a variety of different cannabinoids.

When THCA synthase acts on CBGA, it converts the molecule into—you guessed it—THCA. Consuming raw cannabis supplies users with high levels of this cannabinoid acid. However, cooking and smoking cannabis catalyses a non-enzymatic reaction called decarboxylation.

This process ejects a carboxyl group from the molecule, forming THC. Although these cannabinoids are closely related, they produce profoundly different effects on the body and mind.


THCA and THC are similar in some ways, and dramatically different in others. Check out the lists below to find out where they are alike, and where they differ.

Properties of THCA:

  • Non-psychoactive
  • Naturally occurs in raw cannabis
  • Weak activator of CB1 and CB2 receptors
  • Represents up to 90% of the total THC content of cannabis plants
  • May provide soothing and neurological effects

Properties of THC:

  • Exerts psychoactive effects
  • Produced through decarboxylation
  • Stronger activator of the CB1 receptor
  • Synergises with numerous cannabis terpenes including pinene, limonene, caryophyllene, and linalool
  • Associated with several benefits including relaxation, sleep and appetite promotion, and euphoria

THCA: A Key Biomarker

THCA serves as an important biomarker when it comes to cannabis testing. Ambitious breeders looking to sell their flowers to dispensaries need to test their products beforehand. The more data, the better!

Testing for the level of THCA within a weed sample will give the breeder an accurate picture of how potent their flowers are. Research suggests a 70% conversion rate between THCA and THC during decarboxylation.

Lab technicians need to account for this

30% loss during testing. HPLC (high-pressure liquid chromatography) measures the level of THCA in a precise manner, without decarboxylating any. To figure out the total levels of THC, they use the following equation:

THC total = (%THCA) x 0.877 + (%THC)

What Does the Research Say About THCA?

Research on THCA remains preliminary, with most studies being conducted on animals or cells. Until clinical trials emerge, we have to remain sceptical of THCA’s effects on humans. However, the research so far does serve as an indicator of what we can expect.

Weight Loss

Research conducted in mice suggests that THCA might help to shift a few pounds. A 2020 study [1] showed the cannabinoid to drive down fat mass in mice by interfacing with the PPARy receptor.

May Soothe Joints

THCA may help to soothe joints [2] and other parts of the body through its action on PPARy and the CB1 receptor of the endocannabinoid system.


Further early research suggests that THCA might help to ease a queasy stomach [3] . Although not yet fully substantiated, this finding could make THCA an important agent in the future of cannabis science.

Organ Health

Additional research explored the effects of THCA on liver health [4] in mice. The results showed promise, serving as the groundwork for much more future work in this area.

How to Consume THCA

THCA needs to be consumed in the absence of excess heat. Pure crystalline extracts are one of the best ways to take the cannabinoid. They can easily be added to cool foods and drinks, or mixed with oils and tinctures.

Cannabis users also juice raw cannabis flowers to obtain THCA. Cold-pressed juices work the best, exposing the plant material to less heat.

Where to Get THCA

The best source of THCA is your own cannabis flowers! These resinous buds are packed with the cannabinoid before you hit them in a joint or bong. Fire up your juicer instead to feel the effects of this molecule.

Those lucky enough to live somewhere with a legal recreational cannabis market will also be able to pick up THCA crystals from certain dispensaries.

THC exists as THCA in raw cannabis flowers. It's not until smoking or cooking that THCA converts into the most psychoactive component in the cannabis plant.