BY DR. GENESTER WILSON-KING AND SARAH RUSSO
Whole plant (or broad-spectrum) CBD is cannabidiol that is naturally extracted from the entire cannabis plant. This means it not only contains CBD (if it is a CBD dominant plant) and other cannabinoids, but also terpenes, flavonoids, and additional botanical compounds. The end product is minimally refined, leaving most of the cannabinoids and terpenes intact.
CBD isolate, also called single-molecule CBD, is just that. CBD is the only substance in the preparation. It has been purified and separated from other components in the plant. They are generally labeled as being 99% (or more) “pure” CBD. They have no other active ingredients. 
Isolated CBD has the advantage of standardized dosing and may be beneficial for some people. However, this has its limitations.  Research and anecdotal user feedback have reported that the synergistic effects of various cannabis compounds may help to potentiate its therapeutic potential. Whole plant CBD products (when produced responsibly and properly labeled) have been found to be more effective than isolated products. 
However, there is a place for CBD isolates. Some patients require higher doses of cannabidiol, such as those with seizure disorders or cancer. If larger doses are required, whole-plant CBD can be expensive. Cannabidiol isolate products are more affordable, and therefore may enable people to continue dosing at higher amounts. 
Both whole plant and CBD isolate products can be useful. However, studies have shown that the whole plant CBD has a wider range of effectiveness, especially at lower doses. The premier study demonstrating this finding was done in 2015 in Israel.  A preclinical (mouse) study compared the use of purified cannabidiol isolate to a whole plant CBD dominant chemovar called Avidekel. They found the CBD isolate had a narrow therapeutic window of effectiveness, while the whole plant was effective at a wide range of doses, especially lower doses. Other studies have confirmed these findings. [5,6]
WHAT ABOUT “FULL-SPECTRUM” OR “BROAD-SPECTRUM”?
The words “full-spectrum” and “broad-spectrum” are used interchangeably but they are not synonymous. To add to the confusion, full-spectrum and broad-spectrum mean different things to different people. Full-spectrum generally means there is no THC at all (0%). Full-spectrum can be a misnomer because some components are generally lost during the extraction process.
Broad-spectrum generally incorporates “the whole plant”, including varying amounts of THC.3 This process works to preserve the wide diversity of components of the plant. This distinction between full and broad-spectrum has been reported by Dr. Dustin Sulak of Healer.com. However, there are various other sources that state the opposite. In conclusion, full-spectrum and broad-spectrum are marketing terms that are ill-defined.
Be cautious and make sure you check the Certificate of Analysis (COA) so that you know what type of cannabidiol you are purchasing. Look to see if the company is using CBD isolate or is incorporating the whole plant in its product. And also consider why you are using CBD and the outcome you hope to achieve.
This article originally appeared on the Treadwell Farms blog.
- Sulak, Dustin. Healer Certified Program. Accessed on 5/28/2020.
- Devitt-Lee, Adrian. (2019). “Dosing Pure CBD”. Project CBD
- Healer.com. (2018). CBD & CANNABIS DOSAGE GUIDE – Project CBD Interview with Dr. Sulak. Healer. Accessed on 5/28/2020.
- Gallily, R., Yekhtin, Z., & Hanuš, L. O. (2015). Overcoming the bell-shaped dose-response of cannabidiol by using cannabis extract enriched in cannabidiol. Pharmacology & Pharmacy, 6(02), 75.
- Maa, E., & Figi, P. (2014). The case for medical marijuana in epilepsy. Epilepsia, 55(6), 783-786.
- Sarris, J., Sinclair, J., Karamacoska, D., Davidson, M., & Firth, J. (2020). Medicinal cannabis for psychiatric disorders: a clinically-focused systematic review. BMC Psychiatry, 20(1), 24.
- Cadena, Aaron. (2019). “Full Spectrum vs Broad Spectrum vs CBD Isolate: The Difference Explained”. Medium. Accessed on 5/28/2020.