The Silent Strain: Mounting Evidence Shows Marijuana’s Hidden Dangers to the Heart and Vascular System
As recreational marijuana use grows across the United States and perceptions of its safety become more relaxed, a wave of recent scientific research is sounding the alarm—highlighting the significant cardiovascular risks linked to marijuana consumption, both smoked and ingested.
New Data: A Wake-Up Call for Public Health
A groundbreaking 2025 study from the University of California, San Francisco, published in JAMA Cardiology, uncovered that both smoking marijuana and consuming THC-laced edibles impair vascular function at rates comparable to tobacco use. Participants who regularly used cannabis showed up to a 56% reduction in blood vessel function, a critical measure of cardiovascular health (People, 2025).
Endothelial cells, which line blood vessels and help regulate blood pressure and clotting, were notably damaged in marijuana users. These effects were seen in both smoking and edible users, challenging the myth that edibles are a safer alternative.
Heart Attack and Stroke Risk: Even Occasional Use Raises Red Flags
An observational study supported by the National Institutes of Health (NIH) examined data from over 435,000 U.S. adults. The results were alarming:
Daily marijuana users had a 25% higher chance of a heart attack
The risk of stroke jumped by 42%
Even weekly use increased heart attack risk by 3% and stroke risk by 5% (NIH, 2024)
These findings suggest that cardiovascular damage isn’t limited to chronic users. Even moderate use may carry significant health risks.
Why the Public Messaging Is Failing
The normalization of cannabis, especially among youth and young adults, is colliding with growing data showing that marijuana is not the benign substance many believe it to be. The American Heart Association has echoed these concerns, warning that marijuana’s effects on heart rhythm, blood pressure, and inflammation can create dangerous conditions—especially for people with underlying health issues.
Dr. Thomas Münzel, a cardiovascular researcher in Germany not affiliated with the UCSF study, summarized the problem succinctly: “People think cannabis is natural, so it’s safe. But the data is telling us something very different.”
What This Means for Policy and Health Guidance
As more states legalize recreational cannabis, public health campaigns and clinical providers must be equipped with accurate data and messaging. The idea that marijuana is a harmless lifestyle choice may be leading millions into a false sense of security.
Policy makers must act swiftly to ensure that accurate warnings about cardiovascular risks are included in state and federal health advisories—similar to those issued for tobacco.
References
National Institutes of Health. (2024, November 6). Smoking cannabis associated with increased risk of heart attack and stroke. https://www.nih.gov/news-events/news-releases/smoking-cannabis-associated-increased-risk-heart-attack-stroke
People Magazine. (2025, May 29). THC edibles and smoking weed are linked to early heart disease, according to a new study. https://people.com/thc-edibles-linked-early-heart-disease-study-11744589
SFGate. (2025, May 30). UC San Francisco study uncovers troubling new cannabis health risk. https://www.sfgate.com/cannabis/article/ucsf-cannabis-heart-health-risks-20349621.php
New York Post. (2025, May 30). Weed increases risk of major health issue — even without smoking. https://nypost.com/2025/05/30/health/weed-increases-risk-of-heart-issues-even-without-smoking
