Published in the journal New Phytologist, the researchers found that high-CBD plants inherit about 90% of their genes from drug-type cannabis and the rest from hemp. Traditionally, cannabis plants are split into two varieties: a drug-type grown for psychoactive or intoxicating properties (i.e., marijuana) and a hemp-type used to make industrial products like fiber.
“This poses a challenge, though,” said study co-author and CBS graduate CJ Schwartz of Sunrise Genetics. “The genes that allow for the production of CBD are also a bit ‘leaky.’ This can result in about 5% of the product ending up as THC instead of 100% CBD.”
The researchers examined different types of cannabis, including drug-type varieties that produce large amounts of psychoactive tetrahydrocannabinol (THC). Plant breeding has increased the THC level to the point where it can account for up to a quarter of a plant’s total weight. The scientists found that breeding high-THC plants with hemp-type plants can swap a few genes and make a new plant that produces high levels of CBD instead.
Researchers say this means that when high-CBD plants are grown to full maturity, farmers interested in producing hemp for CBD run the risk of their crop crossing over the federal, legal limit of 0.3% THC.
Research indicates that full-spectrum CBD, whether extracted from hemp or marijuana, may offer enhanced therapeutic benefits.
“I treat patients with both hemp and marijuana CBD products and I couldn’t say one is more effective than the other. I can concur that most of my patients find that having THC, even the 0.3% found in hemp-derived CBD products, is more effective than products with 0% THC,” Damas said.
One critical point of difference between hemp-derived CBD and marijuana-derived CBD is the resin content of each plant. Photo by: Gina Coleman/Weedmaps
The entourage effect
CBD isolate products are those which contain only the CBD molecule, with no accompanying terpenes, THC, or other cannabinoids. For patients with certain medical conditions, or those wishing to avoid THC, CBD isolate may be preferred. The alternatives to CBD isolate would be whole-plant CBD oil, full-spectrum CBD oil, or broad-spectrum CBD oil.
“Full-spectrum [CBD oil] is the extraction of all of the components — cannabinoids, terpenes, flavonoids, etc. — of the hemp plant including low levels of THC,” explained Dr. Chanda Macias, CEO of Women Grow, an organization connecting female professionals in the cannabis industry; and CEO of National Holistic, a healing center based in Washington, D.C.
Which to choose? Experts weigh in
The cannabis species naturally produces hundreds of active compounds. CBD is a chemical compound produced in abundance that has become one of the most commonly sought after cannabinoids. This is largely due to the potential medical and wellness benefits of CBD.
Similarly, Macias pointed out that there are medical conditions that respond only to CBD with varying levels of THC, while other conditions do not require the use of THC to achieve medicinal effects.