Why Crude Whole Plant Cannabis Extracts are Superior to Distillates and Isolates
The health and medicinal benefits of many fruits, vegetables and other plant foods are the result of synergy between the various nutrients and bioactive compounds within the food rather than a single component alone (1). Similarly, cannabis exerts its medicinal effects through synergistic interactions (“entourage effects”) among the various cannabinoids and other phytonutrients it contains.
Examples of the cannabis entourage effect can be found in the scientific literature:
In a rat model of neuropathic pain, a cannabis crude extract containing multiple cannabinoids along with other non-cannabinoid compounds including terpenes and flavonoids provided better and total relief of neuropathic pain compared to an extract of the pure cannabinoids alone (2).
In pain studies conducted in mice, pure CBD produced a biphasic (bell-shaped) dose-response curve where smaller doses of CBD reduced pain until a peak was reached. Higher doses were found to be ineffective. However, when a full spectrum cannabis extract with equivalent doses of CBD was given, a linear dose-response curve was observed – meaning the extract was analgesic at any dose with no observed ceiling effect (3). Other examples of the cannabis entourage effect have been reported including (4).
When making medicinal cannabis extracts, the most healthful and phytonutrient-rich oils can be attained when the whole plant is minimally processed to produce a crude extract that retains the true full spectrum of cannabinoids, terpenes, flavonoids, fatty acids, phenolic acids and other miscellaneous classes of compounds and their metabolites. Distillation, winterization, additional processing and purifying of cannabis oils to remove waxes, chlorophyll and other unwanted plant materials also removes or degrades to varying degrees valuable medicinal plant components. Manufacturers using these stripped down extracts will sometimes add back lab-synthesized or processed terpenes and call the final extract “full spectrum” though this is a far cry from a true full spectrum product.
Why do we want to keep these phytonutrients in our cannabis extracts?
Scientific studies conducted on other medicinal plants can help further our understanding of the pharmacological effects of many of the non-cannabinoid compounds found in cannabis. For example, terpenes form the largest group of non-cannabinoid phytochemicals in cannabis. They are the source of variable aromas, flavors, and other characteristics in the plant kingdom and some of their biological effects have been well characterized. Approximately 200 terpenes have been identified in cannabis and their presence helps to differentiate between the various cannabis chemovars (strains). The most common primary terpenes found in cannabis are β‐caryophyllene, D-limonene, myrcene, α‐pinene, humulene, linalool, limonene, terpinolene, terpineol, ocimene, valencene and geraniol. Some of the more common secondary terpenes in cannabis include α‐bisabolol, nerolidol, caryophyllene oxide, phytol, borneol, δ‐3‐carene, terpinene, camphene, sabinene, cineole (eucalyptol), phellandrene, guaiol, isoborneol, cedrene, geranyl acetate, fenchol, camphor, menthol, isopulegol, cymene, citral, and citronellol. Less common terpenes, some of which have yet to be fully characterized, may also possess medicinal properties that could enhance human health and wellbeing.
Terpenes have been shown to exhibit a variety of biological activities including anti‐inflammatory, anti-oxidant, analgesic, anxiolytic, antidepressant, anti‐insomnia, cancer chemopreventive, antiviral, antibacterial and antifungal effects, to name a few. They may also influence the binding of THC to CB1 receptors, and interact with other neurotransmitter receptors that contribute to cannabinoid‐mediated analgesic effects.
Flavonoids are polyphenolic compounds that normally act as antioxidants in plants and protect against oxidative stress. They also contribute to the vibrant colors in many fruits and vegetables, as well as the beautiful hues found in some cannabis chemovars. Among the approximately 20 flavonoids identified in cannabis include apigenin, luteolin, quercetin, kaempferol, cannflavin A, cannflavin B, β‐sitosterol, vitexin, isovitexin and orientin. Many of these compounds have been shown to have anti‐inflammatory, anti-cancer, anti-hyperalgesic, antifungal and antibacterial effects, to name a few. Epidemiology studies have found correlations between dietary polyphenolic compound intake and reduced incidence of chronic diseases such as neurodegenerative diseases, cancers and cardiovascular disease.
Other phenolic compounds found in cannabis include the stilbenes, phenolic amides, and lignans. A laundry list of other compounds have been identified in cannabis, some of which their potential medicinal benefits have yet to be determined (5).
The final take home message: Whole plant cannabis extracts contain a complex mixture of natural cannabinoids and other non-cannabinoid compounds that may interact synergistically to provide a superior medicinal/therapeutic profile over that of isolated components.
1) Liu RH. Health-promoting components of fruits and vegetables in the diet. Adv Nutr. 2013;4:384S-92S.
2) Comelli F. et al. Antihyperalgesic effect of a Cannabis sativa extract in a rat model of neuropathic pain: mechanisms involved. Phytother Res. 2008; 22(8):1017-24.
3) Gallily R. et al. (2014). Overcoming the bell-shaped dose-response of cannabidiol by using cannabis extract enriched in cannabidiol. Pharmacol. Pharm. 6 75–85.
4) Blasco-Benito S, et al. Appraising the "entourage effect": Antitumor action of a pure cannabinoid versus a botanical drug preparation in preclinical models of breast cancer. Biochem Pharmacol. 2018;157:285-293.
5) C E Turner M A Elsohly E G Boeren. Constituents of Cannabis sativa L. XVII. A review of the natural constituents. Journal of Natural Products. 1980, Vol. 43(2), p.169-234