Have you ever wondered what makes cannabis smell the way it does?
There is a lot of chemistry when it comes to terpenes. There is still a lot to unlock about how our bodies process the chemicals that make things smell. We call these chemicals aromatics and terpenes are the specific types of aromatics produced by plants including cannabis.
Many recent advancements in the science of biology and biochemistry have opened windows into how we experience terpenes. Most people can tell the difference between the smell of lemons and mushrooms because the chemicals they produce interact with our bodies differently. They interact with our endocannabinoid system through CB-1 and CB-2 receptors the same way THC and CBD do.
How do terpenes work?
Terpenes have a synergistic effect with cannabinoids as their complex chemistry is able to shift and flex. Because of their flexibility, they can be used by the body to work for many different uses. Terpenes can affect dopamine and serotonin production and destruction while limonene can increase serotonin production. This is why different strains not only smell and taste different, but also have different affects on mood or sensation.
While over 200 terpenes occur in different concentrations in any given strain, there are a few primary terpenes that produce the greatest concentrations, and about 20 more secondary terpenes that occur in lesser concentrations. Each terpene has a specific purpose and more research is needed to reveal the true complexity of their chemistry.
What are the primary terpenes?
Of all the hundreds of terpenes, there are only a few that are produced in any great abundance. There are about 12 main terpenes in cannabis. Different strains produce terpenes in different amounts and are therefore specialized to treat different maladies. Here are the most common terpenes and what they do.
Myrcene: Is an effective anti inflammatory. It also works as a sedative and muscle relaxer.
Linalool: Can be used as an anti inflammatory and can also modulate motor movements.
Limonene: Can be used to help promote weight loss, prevent and treat cancer, and treat bronchitis.
Alpha Bisabolol: Can heal wounds, fights bacteria, and can also be used a deodorizer.
Delta 3 Carene: Is an effective anti inflammatory. It is also known to dry fluids like tears, running noses, and menstrual flows.
Borneol: Can be used as an analgesic, anti-septic, and bronchodilator.
Pinene: Has anti-inflammatory properties.
Eucalyptol: Is used in cough suppressants, mouthwash, and body powder.
Terpineol: Contains antioxidant properties.
Caryophyllene: May help treat anxiety and depression.
Camphene: Is known to possess anti-inflammatory and antibiotic characteristics.
Testing for terpenes can be done two ways.
Most consumers have a passing knowledge of what terpenes they want. They try a few strains and develop a preference for one over another. A quick sniff of a sample is all that is needed for a broad sense of what is present. Trying to peel apart the individual layers takes a more nuanced approach though.
Myrcene and linalool are some of cannabis’s most abundant terpenes. Myrcene smells musky, like cloves or an earthy, herbal scent. Some even say it has notes of citrus and tropical fruit. Linalool on the other hand smells like a candy or a sweet floral element. The more fragrant a strain, the more terpenes are present and active.
Because of how many different aromatic terpenes cannabis produces, it can be difficult to determine the exact mix of terpenes by smell alone. Most producers or distributors rely on chemical analysis. They get the exact level of terpenes through a report from a certified testing lab. The same labs that test for THC and CBD content are often equipped to also perform terpene analysis for a small fee.
Plants produce terpenes for a variety of reasons.
Plants can’t run away from predators or bad weather. Because they can’t flee, they have developed many ways to deal with the inevitable. One of the ways plants cope is by producing chemicals like cannabinoids and terpenes. Terpenes like pinene and limonene are able to ward off plant predators while linalool and myrcene can help the plant heal from injury.
Plants can also use terpenes to call for help. There is evidence that even corn uses terpenes like those found in cannabis to protect itself from predators. It doesn’t use the terpene to kill anything, it uses it to call for reinforcements. Corn roots damaged by pesky caterpillars emit caryophyllene. This terpene attract predatory wasps that then attack the caterpillars.
Different plants produce the same terpenes.
Cannabis produces terpenes in the same trichomes that it uses to produce cannabinoids like THC and CBD. The cannabis plant smells strongest during flowering because that is when the most trichomes are active. Natural variation and forced breeding techniques have allowed people to design plants based on cannabinoid content as well as terpene content.
Biology is complex but there are repeating patterns. Most plants require the same chemicals (Nitrogen, Phosphorus and Potassium) as they do to produce smells (terpenes). Cannabis produces the same terpenes as other plants, just in different amounts.
Terpenes enhance the effects of cannabinoids.
Take myrcene, it occurs in fragrant plants and herbs like mangoes, hops, bay laurel leaves, thyme, lemongrass, and basil. It is naturally synergistic with THC and allows cannabinoids to more easily bridge the blood-brain barrier. Myrcene is present in most cannabis although it is a dominant terpene in Pure Kush, Jack Herer and many other strains.
Over generations of breeding, cannabis cultivators have selectively bred plants to produce high levels of specific mixes of terpenes. Strains like Lemon Skunk and Sour Lemon have higher levels of limonene in them while Dog Walker and Skunk normally produce more myrcene.
Do terpenes just make things smelly?
Terpenes determine many of the effects attributed to specific strains. While two samples may have the same THC content, if their terpenes profile (mix of terpenes present) are different, the samples will affect someone in different ways. Strains like Granddaddy Purps or OG Kush are generally sedating while Sour Diesel and Strawberry Cough tend to increase alertness.
Humans have inhaled terpenes, including linalool, since ancient times to help relieve stress, fight inflammation, and combat depression. Linalool specifically has been the subject of many studies. Some, like this one where scientists had lab rats inhale linalool while exposing them to stressful conditions, reported that linalool returned their immune system stress levels to near-normal.
We still need to do more research to find all of the ways that terpenes interact with our bodies. As legalization sweeps the country, hope for more research funding is growing. For now, people in states that have legalized cannabis in some way can begin doing anecdotal research themselves. Thanks for reading.