Both Smoking and Eating Cannabis Damage Blood Vessel Function, JAMA Study Finds | Research

The takeaway

A JAMA Cardiology study found that both chronic cannabis smoking and THC edible use impair blood vessel function to a degree similar to tobacco smoking, though through different mechanisms.

Cannabis users concerned about heart health, cardiologists, harm reduction advocates

Blood vessel function: 10.4% (non-users) vs 6.0% (smokers) vs 4.6% (edible users)

What the researchers found

Among 55 participants, cannabis smokers had FMD of 6.0% and THC-edible users had 4.6%, both significantly lower than non-users at 10.4%. Endothelial cells exposed to cannabis smoker serum showed reduced nitric oxide production, but edible user serum did not, suggesting different vascular damage mechanisms.

Why it matters

This is the first study to show that THC edibles, not just smoked cannabis, impair vascular function. The JAMA Cardiology publication signals this finding is considered highly significant by the cardiology community.

The numbers in context

N=55 (20 female, 35 male, mean age 31.3). FMD: smokers 6.0%, edible users 4.6%, non-users 10.4%. Smoker FMD inversely correlated with frequency (r=-0.7). Edible FMD inversely correlated with THC amount (r=-0.7).

How the study worked

Cross-sectional CANDIDE study comparing arterial flow-mediated dilation (FMD), pulse wave velocity, and in vitro endothelial cell function across three groups: chronic cannabis smokers, THC-edible users, and non-users, all non-tobacco-users.

What this study cannot tell us

Small sample size (55 total). Cross-sectional design cannot establish causation. Cannot control for all confounders. Edible users may differ from smokers in ways beyond consumption method. Functional significance of FMD differences not established.

How to read the evidence

Published in JAMA Cardiology with both physiological and cellular measures, but small sample and cross-sectional design limit conclusions.

When this study was published

2025 JAMA Cardiology study with novel findings on edible cannabis cardiovascular effects.

The bigger picture

Many cannabis users switch from smoking to edibles assuming they eliminate health risks. This study challenges that assumption by showing edibles also impair vascular function, potentially through systemic THC effects rather than combustion byproducts.

Questions still open

What is the mechanism by which oral THC damages blood vessels? Is the vascular damage reversible with cessation? Does CBD offset THC's vascular effects?

Common questions

Are cannabis edibles safer for the heart than smoking?

This study found both smoking and eating cannabis were associated with impaired blood vessel function. THC-edible users actually had slightly worse arterial function (4.6%) than cannabis smokers (6.0%), both far below non-users (10.4%).

How does cannabis damage blood vessels?

The mechanisms appear to differ by consumption method. Cannabis smoke seems to damage vessels through reduced nitric oxide production (similar to tobacco), while THC edibles impair vessels through a different, possibly systemic mechanism that needs further investigation.

Read the original research

Association of Endothelial Dysfunction With Chronic Marijuana Smoking and THC-Edible Use.

JAMA cardiology, 10(8), 851-855

View on PubMed ↗Publisher’s paper ↗

Citation

Mohammadi, Leila; Navabzadeh, Mina; Jiménez-Téllez, Nerea; Han, Daniel D; Reagan, Emma; Naughton, Jordan; Zhou, Lylybell Y; Almeida, Rahul; Castaneda, Leslie M; Abdelaal, Shadi A; Park, Kathryn S; Uyemura, Keith; Cheung, Christian P; Onder, Mehmet Nur; Goyal, Natasha; Rao, Poonam; Hellman, Judith; Cheng, Jing; Wu, Joseph C; Marcus, Gregory M; Springer, Matthew L. (2025). Association of Endothelial Dysfunction With Chronic Marijuana Smoking and THC-Edible Use.. JAMA cardiology, 10(8), 851-855. https://doi.org/10.1001/jamacardio.2025.1399