THCA

THCA, or tetrahydrocannabinolic acid, is a cannabis compound that is beginning to demonstrate therapeutic potential despite the infancy of its research. You’ve heard of THC, and while they may sound similar, THCA has very different properties. Unlike THC, THCA is a non-intoxicating cannabinoid found in raw and live cannabis. As the plant dries, THCA slowly converts to THC. Heat expedites this conversion in a process known as decarboxylation, a fancy word that describes what happens when you smoke or vaporize flower.

If you’ve purchased lab-tested cannabis, you may notice that the most abundant cannabinoid is either THC or THCA, either of which can stretch between 10-20% on average. While THCA is the more accurate label for flower that hasn’t been decarboxylated, they essentially mean the same thing if you assume the consumer intends on smoking, vaporizing, or heating the product in some way. But what are THCA’s properties if it isn’t converted to THC?

What are THCA’s effects and benefits?

There isn’t enough research on THCA to definitively state what it can treat and with what degree of efficacy, but preliminary research and anecdotal evidence suggest that THCA will play a pivotal role in cannabis medicine as the industry propels forward. Here are some of the potential benefits studies have started to unveil:

• Anti-inflammatory properties for treatment of arthritis and lupus
• Neuroprotective properties for treatment of neurodegenerative diseases
• Anti-emetic properties for treatment of nausea and appetite loss
• Anti-proliferative properties noted in studies of prostate cancer

Other possible medicinal avenues supported by patient stories include insomnia, muscle spasms, and pain. Unfortunately, we’ll have to wait for more studies to substantiate all of the above benefits before we can fully understand what THCA means for the future of cannabinoid-based medicines.

Why does THC get us elevated and THCA doesn’t?

The reason is due to the shape of the THCA molecule. It is a larger molecule that doesn’t fit into certain cannabinoid receptors, specifically the CB1 receptors. You can find CB1 receptors primarily in the brain, central nervous system, lungs, liver, and kidneys. In order to have an intoxicating effect, a cannabinoid must fit into a CB1 receptor. 

The cannabis plant produces hundreds of cannabinoids, the chemical compounds responsible for the potential 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. So, how does THCA become THC?

How THCA becomes THC

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

Though THCA doesn’t have intoxicating effects, some consider fresh, raw, unheated cannabis a superfood. You may have heard of juicing cannabis or adding raw cannabis to smoothies for health enhancement. There’s a good reason for that.

Much like 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 the following properties:

Anti-inflammatory. A 2011 study published in the Biological and Pharmaceutical Bulletin suggested that, along with other cannabinoids, THCA demonstrated anti-inflammatory properties in lab studies. In a 2021 study using mice, THCA shows great potential as a treatment for fatty liver disease because of its anti-inflammatory traits. 

Neuroprotective. Research, including a study conducted on mice published in 2017 in the British Journal of Pharmacology, points to THCA’s ability to help protect against neurodegenerative diseases.  

Anti-emetic. This is the quality of increasing appetite and decreasing nausea. A 2020 study published in the journal Psychopharmacology found that both THCA and CBDA were effective in reducing nausea and vomiting in rat models, even more so than THC and CBD.
Anti-obesity. A 2020 study that looked at mice and was published in the journal Biochemical Pharmacology demonstrated THCA’s apparent ability to reduce obesity and associated diseases including diabetes and fatty liver disease. As with all of the above findings, more research is needed before drawing any definitive conclusions.

Where can I find THCA?

Every high-THC strain that has not yet been decarboxylated contains THCA, and these cannabinoid levels are particularly high as a live or freshly harvested plant. For this reason, raw cannabis parts are popularly juiced for their THCA benefits (sweet potato pear smoothie, anyone?).

Some products are marketed specifically for their THCA content such as Present Naturals and Mary’s Medicinals transdermal patches. Products like these deliver THCA’s benefits without the risk of psychoactive effects, and as THCA gains traction, we’re likely to find more products like this emerging.

THCA isn’t the only cannabinoid acid

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 potential benefits that are still being discovered. Just like THCA, these cannabinoid acids are unactivated until they go through the decarboxylation process and become capable of interacting with the human ECS.

THCA vs. THC: decarboxylation process

Even though the most common decarboxylation process involves toasting cannabis in the oven to convert THCA into THC, there are many ways that weed can be decarboxylated, or decarbed.

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. When submerged in olive oil, 22% of THCA will convert over the course of 10 days at 77 degrees Fahrenheit (25 degrees Celsius). Under the same conditions, 67% will convert when submerged in ethanol. Over time, cannabis stored at room temperature with a little light exposure will convert 20% of its THCA into THC. Bottom line: THCA is unstable and can convert to THC over time with little intervention. 

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