A recent study has revealed a concerning connection between long-term cannabis use and a heightened risk of cardiovascular disease, irrespective of whether the substance is smoked or consumed as edibles. This finding challenges widespread perceptions regarding the health implications of tetrahydrocannabinol (THC), often considered a relatively benign drug, notably when ingested.

The study, published in the journal JAMA Cardiology on wednesday, May 28, demonstrated that individuals who smoke THC experience notably poorer artery function compared to non-users. A similar effect was observed in those who consume edibles, even though their arteries were not as severely affected. According to a statement from the University of California, San Francisco, vascular function was reduced by approximately half in both cannabis user groups compared to non-users.

Impact on Arterial Function

to investigate the impact of cannabis on vascular function, researchers examined 55 healthy adults between the ages of 18 and 50 who did not use nicotine products and were not regularly exposed to secondhand smoke.

Participants were divided into three groups: cannabis smokers, edible consumers, and non-users.Those in the cannabis user groups reported using the drug at least three times per week, either through smoking or edibles.

The researchers assessed vascular function by measuring the dilation of the brachial artery in the upper arm to determine its ability to expand in response to increased blood flow. an inflatable forearm cuff was used to briefly block blood flow to the artery, and ultrasound was used to measure its diameter before and after inflation.

“scientifically, this THC result is really engaging but boy does it screw up the public health messaging.”

According to Matt Springer, a cardiovascular researcher at UCSF, this test provides a “window into the future,” as he told Live Science. He explained that when blood vessels cannot fully dilate, the risk of heart attack and other adverse cardiovascular outcomes increases.

Study Findings

Participants who did not consume cannabis exhibited an average vessel dilation of 10.4%. This value was considerably lower among cannabis smokers and edible users, with average vessel dilation rates of 6.0% and 4.6%, respectively. Typical brachial artery dilation values in healthy individuals range from 8.0% to 15%. Springer’s lab previously found similarly reduced levels of vessel dilation among e-cigarette and cigarette smokers.

Further lab tests revealed that the blood of chronic cannabis smokers inhibited nitric oxide production in endothelial cells,wich line blood vessels and trigger dilation. This may explain the reduced vessel dilation observed in these participants.

However, this effect was not observed in edible consumers, suggesting that ingestible THC may affect arterial function through a different mechanism. further research is needed to identify this mechanism and validate these findings in a larger population.

According to the National Institute on Drug Abuse, cannabis use among U.S. adults has increased in recent years. As such, research into the health effects of THC is increasingly crucial, especially as evidence mounts against the perception of cannabis as a harmless substance.