Over the past few months, we’ve been diving a little deeper into the various compounds found within Full Spectrum CBD in a series dubbed The Nature of Full Spectrum. Having already discussed cannabinoids and flavonoids, this week we’re exploring terpenes – what they are, how they contribute, and what the science says.

Terpenes are said to contribute to the ‘entourage effect,’ which suggests that when all supporting compounds are present in a cannabis product, they’re able to work together to create a result stronger than the sum of their individual parts. But what are terpenes, and how do they contribute to CBD’s overall effect?

As we’ll discuss, the initial science seems positive, suggesting that terpenes may contribute to our overall health and wellness. However, much of this research is preliminary and not always conducted within the context of CBD or cannabis. Ultimately, this means that we have a long way to go before we can make any substantial health claims. What we can do, however, is discuss the state of terpene science as it currently stands.

What Are Terpenes?

Terpenes, or terpenoids, are the chemical compounds responsible for giving plants a particular aroma. They can be found in a variety of herbs, fruits, vegetables, spices, and more. Terpenes can help keep insects and pests away from plants, offering them a form of protection. Terpenes also form the basis of aromatherapy, or the idea that certain smells are able to impact and influence the health of our bodies. However, it is important to note that although some preliminary studies look promising, the validity of aromatherapy is still largely contested by scientists, particularly within the context of essential oils.

There are many types of terpenes that have been found within cannabis. As the average consumer continues to learn more and prioritize terpene content, we’ve seen priorities start to shift from THC-heavy to terpene-heavy products. These terpenes contribute to a plant’s unique profile, and why one strain is often different from the next. More recently, there’s been some discussion around whether strain names, like Sativa and Indica, provide less information than the specific terpenoid profile of the plant, especially when it comes to any potential physiological effects. For example, differences in terpenoid profiles could possibly help explain why some strains of cannabis or hemp are said to be more energizing while others claim more sedative effects.

Because of this, it can be important to pay attention to a product’s terpenoid profile, hopefully made publicly accessible through the release of a product’s certificate of analysis (COA).

Research Limitations

Many of the studies conducted on terpenes commonly found within cannabis, such as Myrcene and Limonene, have been done outside of the cannabis context, often in isolated, laboratory conditions. While it would be easy to assume that these findings also apply to the terpenes found within CBD, this isn’t necessarily the case. Questions of bioavailability (how much gets absorbed into the body) are prominent, and whether the health benefits associated with terpenes are accessible through the consumption of cannabis isn’t always known. Additionally, much of the research that has been done is through the use of animal studies, with human relevancy receiving less assessment. This means that we need to do a lot more contextually relevant research before we can say anything for certain.

All this is to say, when discussing the current science about terpenes, it is important to recognize the context in which this research has been conducted, particularly so when done outside of the scope of cannabis.

Pinene

Pinene is one of the more common terpenes found within cannabis and is usually broken down into Alpha-Pinene and Beta-Pinene. As the name suggests, Pinene is a big part of pine resin and is also found in a variety of other trees. Within the context of cannabis, there has been some research to suggest that it may help treat pain, insomnia, and depression. Outside of the cannabis context, this research review found evidence to suggest that it may be antibacterial, antitumour, anti-inflammatory, antimicrobial, and more. However, not much is known or has been researched about its bioavailability.

Mycrene

Myrcene is also commonly found in things like lemongrass and hops and tends to have a spicy and earthy scent. There has been research to suggest that it has anti-aging, antioxidant, anti-inflammatory, anti-anxiety, anti-cancer, and pain-relieving properties, both within and outside of the cannabis context. However, more human trials and CBD-specific studies are necessary before we can make any substantial health claims.

Limonene

Limonene is commonly found in the peels of citrus fruits and other plants and can be used for flavoring as well as making medicine, household cleaners, cosmetics, and other hygiene products. Outside of the cannabis context, there has been some research to suggest that limonene has anti-inflammatory, antioxidant, anticancer, antibacterial, neuroprotective, and anti-stress properties. Like some of the above terpenes, however, the research we currently have available relies heavily on animal trials and was conducted outside of the context of cannabis.

Linalool

Linalool is found within lavender, cinnamon, citrus, and over two hundred other plant types. It’s commonly used as a fragrance in cleaning products as well as an insecticide. There has been some research to suggest that linalool has anti-anxiety properties. It is also suggested to have antimicrobial, anti-inflammatory, anticancer, anti-depression, and antioxidant properties. However, not a lot of research has been done with Linalool and CBD specifically.

Caryophyllene

Caryophyllene, more formally known as β-Caryophyllene, is a terpene commonly found in black pepper, oregano, a variety of herbs, and leafy vegetables. Caryophyllene is the only terpenoid known to interact directly with the endocannabinoid system (ECS) and CB2 receptors. Some studies, conducted both within and outside of cannabis, have suggested this interaction may be useful for treating inflammation, pain, diabetes, atherosclerosis, mental health challenges, sexual dysfunction, and osteoporosis. It’s also heavily discussed for its potential antioxidant qualities.

Humulene

Humulene, also known as α-Caryophyllene, is a terpene named after and located within hops, though it can be found in a variety of other plants as well. Some research has suggested that Humulene is antibacterial, while other studies have investigated its anti-inflammatory properties. However, most of these studies were conducted outside of the context of cannabis. Through more CBD-applicable studies, there’s also been some research to suggest that it may exhibit anti-cancer properties.

Ocimene

Ocimene is one of the more popular terpenes found in nature, and may actually be used by plants to help attract pollinators. It can be used to manage bee colonies, impact butterfly mating habits, or trigger cabbage’s defense responses against harmful insects.

More relevant to us, however, in animal studies, it’s been shown to have anti-inflammatory properties. It may also exhibit anti-fungal traits, while this in vitro study suggests that it may be able to act as a potential defense or support against Leishmaniasis, a group of dangerous parasitic diseases.

Within the food and nutritional context, ocimene was identified as one of the compounds within various Lebanese spices and may exhibit antiviral properties. According to this study, it was also located within black pepper, and along with a variety of other terpenes, may exhibit antioxidant qualities as well as impact enzymes associated with type 2 Diabetes. Unfortunately, there doesn’t seem to be a lot of research conducted within the cannabis context.

Geraniol

Geraniol is another common compound, often being used in fragrances, household items, and insect repellants. It may help support other substances to be better absorbed by our skin, and in preclinical trials, seems to exhibit possible antimicrobial, anti-cancer, anti-tumor, anti-depression, and anti-inflammatory properties. However, toxicity is still a potential concern, especially when mixed with other medications or treatments. Unlike a lot of compounds, there has been some research into geraniol’s bioavailability, which so far seems quite positive. In general, research reviews and studies conducted with geraniol call for more applicable research, including more animal trials, since most research is preclinical and in vitro.

Bisabolol

Bisabolol is often used in hygiene products and cosmetics, and seems to have a relatively safe profile. Both in vitro and in vivo studies show antioxidant, anti-inflammatory, anticancer, antimicrobial, and neuroprotective properties. This study, done within the cosmetic context, found that bisabolol can help soothe skin after irritants, such as UV rays or insect bites. However, studies are lacking, especially within the cannabis context, and we have a ways to go before we can begin clinical trials.

TL;DR

Terpenes contribute to a plant’s unique smell and are an important part of what differentiates strains of cannabis or hemp from each other. In terms of CBD, terpenes play a role in the entourage effect. However, most of the terpene science we have available to us is still preliminary, with much of it originating from outside the context of cannabis. This means that while current research seems positive, we have a lot more to learn before we understand terpenes and the effect they play within CBD.