CBD did not prove effective in counterbalancing the effects of delta-9 THC on brain connectivity, and may heighten them, according to a recently published study.
Contrary to earlier research suggesting that CBD might tamp down THC’s psychoactive effects, the study found that adding CBD to THC not only failed to mitigate disruptions in neural connectivity but, in some cases, made them stronger.
Carried out by researchers from the University of Bath and University College London, the study, published in the journal Neuropsychopharmacology, found that a THC+CBD mixture could intensify disruptions in brain networks that are active during rest.
The research team examined the effects of cannabis on the brain networks of adolescents and young adults using magnetic resonance imaging (MRI). Cannabis significantly disrupted functional connectivity in key brain regions responsible for day-to-day functions, decision-making, and memory, as well as areas responsible for processing emotions and important sensory information, the research found.
“Our findings suggest that CBD does not attenuate THC effects,” the study reported, “and in some cases, potentiated them.
“THC+CBD reduced connectivity significantly more relative to THC alone,” the researchers observed.
They vaped the stuff
The study involved 46 participants: 22 adolescents aged 16-17, and 24 young adults aged 26-29. Participants inhaled vaporized cannabis containing either THC, a combination of THC and CBD, or a placebo before undergoing MRI scans. Both THC and the THC+CBD combination led to significant decreases in communication between the key brain networks studied.
Despite the rapid brain development that occurs during adolescence, the researchers found no significant differences in cannabis’ effects between adolescents and young adults.
“Cannabis causes similar disruption to resting-state connectivity in the adolescent and adult brain,” the study noted, challenging earlier assumptions that adolescents are more vulnerable to cannabis’ effects.
These findings suggest that CBD’s role in moderating THC’s effects may depend on dosage or other factors not yet fully understood. While CBD has been marketed as a therapeutic compound with potential benefits like reducing anxiety and addiction, this study underscores the need for further research, particularly in relation to its interaction with THC at different concentrations.
Inform yourself
The implications of this study are significant for public health, particularly as more countries and regions legalize cannabis products with varying THC and CBD ratios. Many users opt for cannabis strains high in CBD under the assumption that they are safer or produce fewer negative effects. However, this study challenges that assumption and highlights the need for consumers to be better informed about the possible risks of combining THC and CBD.
“Given that public health guidelines often recommend using cannabis with high CBD: THC ratios, our findings suggest this advice may need revisiting,” the authors concluded. As regulatory bodies and health professionals develop guidance for cannabis use, understanding the intricate effects of THC and CBD on brain connectivity will be critical for creating safer consumption practices.
While CBD is generally considered to be a less harmful component of cannabis, its interactions with THC may be more complex than previously believed. The findings open the door to further investigations on how cannabinoids interact and their long-term impacts on the brain, particularly during critical developmental stages.
The authors said the study is intended to provide essential insights into the cognitive and neural effects of cannabis, informing both medical research and public health policy.
Neuropsychopharmacology is published by London-based Springer Nature on behalf of the American College of Neuropsychopharmacology.