by Dr. Bill Rawls
Posted 6/27/19

Terpenes, the natural compounds in plants that give them their scents and flavors, may hold the key to maximizing the health benefits of full-spectrum cannabidiol or CBD oil from the hemp plant.

Even if you’ve never taken CBD oil or heard of terpenes, you’ve definitely come across the compounds and inevitably benefited from them: If you’ve ever burned a lavender candle to help promote relaxation, used citrus-scented dish soap to pep up a cleaning session, or breathed deep in a densely-wooded forest and felt invigorated, you’ve experienced the subtle but meaningful effects of terpenes.

Emerging research shows terpenes play a role in how our body’s endocannabinoid system (ECS) reacts with other plant compounds, so let’s take a look at terpenes in full-spectrum plant extracts.

What Are Terpenes?

Terpenes are a class of organic compounds found in a wide variety of plants. Plants communicate through terpenes, attracting pollinators via their fragrances or repelling potential attackers with unpleasant tastes or a toxic component as a defense mechanism.

Plants produce terpenes for other reasons, too. Some of these compounds protect plants from fungus, mold, and other environmental stressors. These properties mean terpenes have value for humans as well, which is why terpenes have been part of the herbal-medicine toolkit for centuries.

Today, terpenes are widely used in food products and cosmetics, as well as by the pharmaceutical and biotechnology industries. Recent scientific studies have spurred new interest in the impact terpenes can have on human health and wellness, and emerging research indicates these plant compounds could play a vital role in the efficacy of CBD medicine.

How Do Terpenes Affect Us?

The number of terpenes produced in the natural world is vast, and deeper scientific exploration of terpenes is a fairly recent undertaking. In 2001, estimates of the number of identified terpenes were in the neighborhood of 20,000; by 2013, estimates were pegged at upwards of 55,000.

Despite the relative newness of this area of research, findings thus far have proven very promising. Researchers have determined some terpenes are analgesic (pain-relieving), some are antifungal, and some are anti-inflammatory, among other properties.

In a detailed reference book compiled by botanists called Natural Products: Phytochemistry, Botany and Metabolism of Alkaloids, Phenolics and Terpenes, the editors highlight the “important therapeutic uses of terpenoids,” which include cancer treatments as well as “antimicrobial, antifungal, antiviral, antihyperglycemic, anti-inflammatory, antioxidant and antiparasitic, immunomodulatory, and as skin permeation enhancer.”

Indeed, many studies back up long-held folk medicine beliefs about the healing potential of plant medicine. A famous Korean forest-bathing study made headlines after its publication in 2017, in part because its examination of terpenes offered scientific evidence of a phenomenon many of us have experienced: Breathing the air of densely wooded, plant-heavy natural spaces makes us feel better. The researchers noted:

In addition to mood-boosting abilities, some terpenes may actually improve our brain function. The herb rosemary, which contains many terpenes, including pinene, caryophyllene, limonene, and linalool, has long been associated with improved memory (Shakespeare even references the connection in Hamlet). In a recent study by the United Kingdom’s Northumbria University of 150 healthy seniors, those who had breathed rosemary oils showed significantly enhanced memory and alertness, scoring 15% higher on memory tests than the control group.

Terpenes such as linalool, a compound found in large quantities in lavender, could play an important role in pain management. In one 2007 study, 54 patients who had just undergone the same surgical procedure were given either lavender oil vapor or a placebo to inhale. So how did their experiences differ?

While 82% of the patients in the placebo group needed to take analgesics to manage their postoperative pain, only 46% of the lavender oil group did. The lavender group needed less postoperative morphine than the control group as well. Though researchers concluded further study was needed, they argued that “results suggest that lavender aromatherapy can be used to reduce the demand for opioids in the immediate postoperative period.”

Other research has shown terpenes could affect moods in a positive manner. One such study found caryophyllene reduced the behavioral symptoms of anxiety and depression in animals. Several other studies on animal models and humans have shown that terpene-rich lavender effectively ameliorates generalized anxiety as well as widely used anti-anxiety medications.

How Does the Entourage Effect Work?

When choosing a CBD formulation, full-spectrum CBD is often recommended, in part because of its terpene content. Many experts argue that CBD isolate, a formulation of pure CBD from which all other plant compounds have been removed, doesn’t work as effectively in patients because it lacks the other beneficial compounds present in the original plant.

This comes down to the way the body’s endocannabinoid system (ECS) works. The ECS — a series of receptors located throughout the body — is responsible for maintaining homeostasis in a number of functions, from metabolism to pain sensing to mood regulation, among others.

Full-spectrum CBD, also called whole-plant CBD, retains the many other phytocannabinoids and terpenes in the plant. Studies indicate the terpenes in full-spectrum CBD work synergistically with the other cannabinoids and plant compounds. In a groundbreaking 2011 study, Dr. Ethan Russo argued that terpenes “display unique therapeutic effects that may contribute meaningfully to the entourage effects of cannabis-based medicinal extracts.”

This increased efficacy is known as the “entourage effect.”

The entourage effect is attributed to the way the ECS interacts with molecules such as terpenes and cannabinoids, whether they are produced by the body (endocannabinoids) or plants (phytocannabinoids). Researchers have only recently begun to drill into the ways plant compounds work alone and in concert.

The Health Benefits of Native Terpenes

Native terpenes — the natural compounds in plants like hemp that give them their scents and flavors — are proving to have numerous health benefits. That’s especially true when the terpenes are part of a full-spectrum extract that enables the “entourage effect,” a phenomenon where plant compounds work together more synergistically for more meaningful effects. Here’s just a sampling of the benefits of specific terpenes discovered so far by researchers.

Eucalyptol: anti-inflammatory; relieves respiratory symptoms
Antioxidant and anti-inflammatory action helps calm spasms in the respiratory tract and clear mucus, suggesting eucalyptol can help improve symptoms of respiratory conditions such as asthma.

Linalool: improves memory and alertness; eases pain
Long associated with improved memory and alertness, linalool is also associated with reduced pain after surgery as well as reduced symptoms of anxiety and depression.

Caryophyllene: eases anxiety and depression; improves memory
Like linalool, caryophyllene has been shown to help reduce generalized anxiety and depression and increase memory and alertness.

Myrcene: synergistically enhances actions of other terpenes
This terpene has been shown to help synergize the activities of other terpenes and plant compounds in several ways, pointing again to the importance of a full-spectrum extract for the entourage effect.

Delta 3 Carene: anti-inflammatory; antifungal; promotes bone health
Research links this terpene with the ability to help reduce acute inflammation, promote bone health, and act as an antifungal agent in partnership with pinene, another terpene.

Pinene: antimicrobial
A potent antimicrobial terpene, pinene has been shown to be effective in suppressing P. acnes and certain strains of Staphylococcus including antibiotic-resistant strains like MRSA.

Delta Limonene: promotes healthy digestion; eases GI symptoms
One of the most common terpenes in nature, delta limonene has been shown to help neutralize gastric acid, support normal peristalsis (the movement of food through the digestive tract), and relieve symptoms of heartburn and gastroesophageal reflux (GERD).

Terpinolene: slows tumor cell growth
Preliminary research suggests terpinolene helps slow the growth of brain tumor cells, making it a potential candidate for addressing cancer.

Beta-Caryophyllene: anti-inflammatory; promotes GI health
An anti-inflammatory terpene, beta-caryophyllene has been shown to help soothe the GI tract and is often found in soothing topical salves.

Humulene: topical and systemic anti-inflammatory
Also known as alpha-carophyllene, humulene has been shown to have both topical and systemic anti-inflammatory properties.

Should You Increase Your Terpene Intake?

In short, yes! Terpenes can be ingested through a plant-rich diet and full-spectrum CBD oil from hemp, as well as through essential oils in diffusers or nature hikes.

Because terpenes are so widely used in food flavorings and household products, producing synthetic terpenes is a booming business. But when it comes to terpenes as medicine, many experts say patients should choose the natural route: Native terpenes, derived from plants like hemp.

If you recall the recent media firestorm around LaCroix sparkling water, a class-action lawsuit was filed alleging the company added synthetic terpenes to its beverages, as opposed to botanically derived terpenes. Therefore, they weren’t using “natural flavors,” as listed in its ingredients. There’s no hard evidence that synthetic terpenes pose health risks, but most proponents of plant medicine advise consumers to make sure the CBD they’re purchasing only contains compounds derived from plants.

While third-party lab testing and Certificates of Analysis (COAs) can tell you which terpenes the CBD formulation contains and the relative quantities of terpenes in a product, there are no specific recommendations yet from medical authorities on terpene consumption.

As with all of the health potential of hemp, CBD, other cannabinoids, and terpenes, we need more science and further study. But it’s reassuring to know that when you take a walk in the woods, light a lavender candle, or consume a reputable, full-spectrum CBD formulation, you are ingesting important plant compounds that can impact your health for the better.

Dr. Rawls is a physician who overcame Lyme disease through natural herbal therapy. You can learn more about Lyme disease in Dr. Rawls’ new best selling book, Unlocking Lyme.
You can also learn about Dr. Rawls’ personal journey in overcoming Lyme disease and fibromyalgia in his popular blog post, My Chronic Lyme Journey.