A recent study from the University of California, San Francisco (UCSF) reveals that long-term cannabis use, whether by smoking or eating edibles, significantly harms heart health. The research shows that chronic users have much poorer artery function compared to people who do not use cannabis.
Key Points:
- Chronic cannabis use reduces artery dilation by about 50% compared to non-users.
- Both smoking and edible consumption impair vascular function, but likely through different biological pathways.
- Reduced artery dilation is a warning sign for future heart attacks and strokes.
- The study involved 55 healthy adults who used cannabis at least three times weekly.
- More research is needed to confirm findings and understand mechanisms.
- Cannabis use is increasing, making these health risks more relevant.
Published on May 28 in JAMA Cardiology, the study measured how well blood vessels in the arm expand—a key sign of healthy cardiovascular function.
Researchers tested 55 healthy adults aged 18 to 50 who did not use nicotine or have secondhand smoke exposure. They divided participants into three groups: marijuana smokers, edible users, and non-users. Both cannabis groups used marijuana at least three times a week.
The results showed that cannabis users had roughly half the vascular function of non-users. Smokers’ arteries dilated by about 6%, while edible users’ arteries dilated even less, at 4.6%.
In contrast, non-users’ arteries dilated by 10.4%. Healthy arteries typically dilate between 8% and 15%. This reduced dilation signals a higher risk for heart attacks and strokes.
Lead researcher Matt Springer explained that when blood vessels cannot expand properly, it increases the chance of serious heart problems.
The study also found that blood from smokers inhibited the production of nitric oxide, a molecule important for artery dilation. This effect was not seen in edible users, suggesting different mechanisms of harm depending on how THC is consumed.
These findings add to growing evidence linking cannabis use to cardiovascular damage. A 2024 study showed daily cannabis users have a 25% higher risk of heart attack and a 42% higher risk of stroke. Experts warn that the belief that marijuana—especially edibles—is harmless is misleading.
As cannabis use rises in the U.S., understanding its health effects is urgent. Researchers call for more studies with larger groups to confirm these results and clarify how THC affects the heart. Meanwhile, caution is advised for those who use marijuana regularly, regardless of the form.
In summary, this study challenges the idea that cannabis is safe for the heart. Both smoking and eating THC can impair artery function, raising the risk of serious cardiovascular disease.
