When Cannabis is Prohibited, Delta-8 THC Thrives, Researchers Reveal

Well-populated states like Texas, Georgia and North Carolina represent substantial business opportunities for those who cultivate, manufacture or retail cannabis, should prohibitionist policies be reversed.

While North Carolina prohibits medical and adult-use cannabis, many reform advocates don’t recognize Texas and Georgia’s low-THC medical-only cannabis programs because of their restrictive natures.

Florida and Pennsylvania also symbolize catalysts for growth, should they expand from medical-only to adult-use cannabis markets.

With nearly 90 million people living in these five states alone, less permissive cannabis policies don’t necessarily equate to consumers steering clear of intoxicating cannabinoids, especially when consumable hemp THC products provide an alternative.

Adults who live in states that prohibit all forms of cannabis are almost twice as likely (10.9%) to have used delta-8 THC compared to those who live in the 24 states where adult-use cannabis is legal, according to Researchers from the University of California, San Diego. Delta-8 THC is an intoxicating compound that’s often converted in a lab from nonintoxicating hemp-derived CBD.

The UC San Diego researchers, who based their study on a nationally representative survey of 1,523 U.S. adults, found that delta-8 THC is most commonly used in states such as Texas, where adult-use cannabis remains illegal and hemp-derived THC products like delta-8 gummies aren’t held to the same stringent standards as licensed, regulated and taxed cannabis programs.

The university findings were published Sept. 3 in the American Journal of Preventive Medicine. The study’s authors concluded that prohibition “may be inadvertently steering people toward less-regulated substances” and that overregulation in the cannabis sector has motivated product manufacturers to “evade restrictions” through what many view as a loophole in the 2018 Farm Bill.

The UC San Diego researchers also found that American consumers were much more likely to use delta-8 THC in states with no regulations on those sales (10.5%) compared to states that had taken steps to prohibit (4.5%) or regulate (3.9%) the compound.

In addition, they found that American consumers use delta-8 THC less often in states that have legalized medical and adult-use cannabis (5.5%) compared to states that permit medical use only (8.5%), such as Florida.

“These findings underscore that people don’t just stop using cannabis when their state bans it. They often shift to alternatives that are easier to access, even if they’re less well-studied or poorly regulated,” said Eric Leas, Ph.D., M.P.H., assistant professor at the Herbert Wertheim School of Public Health and Human Longevity Science at UC San Diego and senior author of the study. Leas is also an affiliate faculty member at the Qualcomm Institute.

“It’s a classic case of unintended consequences in public policy,” he said in a release announcing the study.

Sen. Mitch McConnell, R-Ky., who championed the federal legalization of hemp as an agricultural commodity for grain, fiber and seeds as a proponent of the 2018 Farm Bill, spoke about the unintended consequences of that legislation in July 2025, when he unsuccessfully attempted to prohibit hemp THC via a federal spending bill provision.

The 2018 Farm Bill specifically defines hemp as having no more than 0.3% delta-9 THC on a dry-weight basis. Delta-9 THC is the main naturally occurring intoxicating compound in cannabis. However, the federal legislation makes no mention of delta-8 THC, which is often synthesized by chemically converting CBD derived from compliant hemp plants.

The U.S. Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC) issued warnings in 2021 that delta-8 THC has “serious health risks.” The FDA continues to send warning letters directly to businesses today. However, delta-8 THC products have largely gone unregulated and continue to proliferate throughout the nation, especially in states that haven’t enacted their own regulatory or prohibitive frameworks.

In 2021, shortly after Connecticut became the 18th state to legalize adult-use cannabis, Leas authored an editorial in which he called for the loophole to be closed.

In the UC San Diego study released this week, Leas called attention to a 2022 study and revealed similar results of delta-8 THC thriving in states with less permissive cannabis laws.  

“The numbers in this study confirm a pattern we have seen before in data on delta-8 THC internet searches published in the International Journal of Drug Policy: when safer, regulated access to marijuana is unavailable, people become interested in products that are available, even if they’re riskier,” Leas said. “Providing legal access to cannabis that meets safety standards and disallowing understudied and poorly regulated products like delta-8 THC could be one way to prioritize public health in our cannabis policies.”

The UC San Diego researchers pointed out this week that when intoxicating hemp-THC products are sold in gas stations, smoke shops and convenience stores, and sometimes packaged in ways attractive to children, it can lead to accidental ingestion and public assumptions that the products are safely regulated.

Although cannabis prohibitionists sometimes claim legalization leads to an increase in youth consumption or calls to poison control centers, the university researchers referenced a 2023 report of rising poisonings specifically tied to delta-8 THC.  

The UC San Diego study’s authors suggested that congressional clarity through redefining hemp in the farm bill’s reauthorization or separate legislation addressing cannabinoids in finished goods could mitigate potential harms associated with delta-8 THC products.

“We need to ensure people aren’t caught in a policy vacuum, relying on products that fall outside both safety regulations and scientific understanding,” Leas said, cautioning that blanket prohibitions may not be the answer.

“We often think banning a product solves the problem. But when the market moves faster than regulation, it can create new problems,” he said. “If we want to reduce harm, we need policies that reflect how people actually behave, not just how we hope they will.”