Can Cannabis Cause a Heart Attack?
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Why are cardiologists suddenly so concerned about cannabis?
Review of a major research study on cannabis
Findings on Cannabis Use in Young and “Healthy” Adults
How might cannabis trigger or contribute to a heart attack?
Practical takeaways if you use cannabis
Summary: So… can cannabis cause a heart attack?
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If you or a loved one is struggling with cannabis use and addiction, please call 6063934632 to schedule an assessment and to learn about treatments options.
Key points
Large population studies now link cannabis use with higher risk of heart attack and stroke, even after accounting for tobacco and other risk factors.
Daily use is where the signal is clearest: studies show ~25% higher odds of heart attack and ~40% higher odds of stroke in daily users compared with non-users.
A huge analysis of adults under 50 without traditional risk factors found cannabis users were 6 times more likely to have a heart attack than non-users.
New vascular studies show that both smoking and edible THC are linked to impaired blood vessel function, an early step toward heart disease.
Why are cardiologists suddenly so concerned about cannabis?
Cannabis use has exploded in the U.S. As laws loosen, use has risen from about 11% of adults in 2002 to roughly 17% in 2019. At the same time, today’s products, especially high-THC flower and concentrates, are far more potent than what was available in the 1990s.
For years, the data on heart risk were scattered and underpowered. That’s changing. New research uses:
Hundreds of thousands to millions of people from national health surveys and health systems.
Careful adjustment for age, blood pressure, cholesterol, diabetes, and tobacco use.
Dose–response analyses (more days of use per month → higher odds of events).
Taken together, they paint a consistent picture: the more often you use cannabis (especially daily) the more your cardiovascular risk climbs.
Review of a major research study on cannabis
One of the most important studies comes from the Journal of the American Heart Association (JAHA). Researchers analyzed data from 434,104 U.S. adults in the CDC’s Behavioral Risk Factor Surveillance System (2016–2020).
They looked at:
Cannabis use – number of days used in the past 30 days (0–30).
Cardiovascular outcomes – self-reported coronary heart disease, heart attack (myocardial infarction), and stroke.
After adjusting for age, sex, BMI, diabetes, blood pressure, cholesterol, alcohol use, and tobacco/e-cigarette use, they found:
Daily cannabis use was associated with:
25% higher odds of heart attack
42% higher odds of stroke
28% higher odds of the combined outcome (heart disease, heart attack, or stroke)
Among people who had never smoked tobacco, daily cannabis use was still linked to:
~1.5× higher odds of heart attack
>2× higher odds of stroke
In summary:
Even when you remove cigarettes from the equation, cannabis alone is associated with more heart attacks and strokes, especially at daily use levels.
The American Heart Association summarized it bluntly: more frequent cannabis use was associated with higher odds of adverse cardiovascular outcomes, and the pattern held even in never-tobacco users.
Findings on Cannabis Use in Young and “Healthy” Adults
Another set of data that’s getting attention comes from a massive analysis presented at the American College of Cardiology (ACC) meeting and published in JACC: Advances. Researchers pulled electronic health records from over 4.6 million adults under 50 who had:
Normal blood pressure
Normal LDL cholesterol
No diabetes
No tobacco use
No prior coronary artery disease
Among this otherwise low-risk group, those who used cannabis were:
>6 times more likely to have a heart attack
4 times more likely to have an ischemic stroke
Twice as likely to develop heart failure
About 3 times more likely to die from cardiovascular causes
This doesn’t prove that cannabis alone is responsible—other unmeasured factors could play a role—but it’s hard to ignore a signal this strong in people who otherwise look “healthy” on paper.
The ACC’s takeaway: asking about cannabis use should be part of routine cardiovascular risk assessment, especially in younger patients.
“But I use edibles, and i’m not smoking, does that make it safer?”
Short answer: it may change how cannabis stresses your heart and blood vessels, but it doesn’t make it harmless.
A study, published in JAMA Cardiology brought in 55 otherwise healthy adults who:
Regularly smoked cannabis or
Regularly used THC edibles
Used cannabis ≥3 times per week for at least a year
Compared with non-users, both groups (smokers and edible users) had:
Vascular function reduced by about half – their blood vessels were less able to dilate (widen) when needed, an early warning sign for heart disease.
This degree of impairment was similar to what you see in tobacco smokers.
Important points:
People who smoked cannabis had blood serum changes that were clearly harmful to endothelial cells (the lining of blood vessels).
People who used edibles did not show those same serum changes—yet their vascular function was still impaired.
So:
Smoking adds all the usual harms of inhaled smoke, plus THC’s effects.
But THC itself (even in edible form) appears to affect blood vessel function in ways we’re only beginning to understand.
The take-home: switching from smoking to edibles may reduce some risks, but it does not erase cardiovascular concerns.
How might cannabis trigger or contribute to a heart attack?
Mechanistically, a few things are happening at once:
THC revs up the sympathetic nervous system
Increases heart rate and blood pressure
Raises the heart’s oxygen demand—like asking your heart to run uphill suddenly
Smoke (from joints, blunts, vapes with combustion) injures blood vessels
Cannabis smoke contains many of the same toxic particles as tobacco smoke
This promotes endothelial dysfunction (stiff, less responsive arteries) and oxidative stress, which set the stage for plaque buildup and clots
Blood flow and oxygen delivery can be disrupted
Increased carboxyhemoglobin (from smoke) reduces oxygen-carrying capacity
Spasm or narrowing in coronary arteries can briefly shut down blood flow—enough to trigger chest pain or even an infarct in vulnerable hearts
Arrhythmias (irregular heart rhythms)
Case reports and small studies link cannabis to atrial fibrillation and other rhythm disturbances, which can themselves trigger clots or worsen heart failure.
None of this proves that one joint automatically causes one heart attack. But if you layer cannabis on top of:
High blood pressure
Diabetes
High cholesterol
Sleep apnea
Strong family history of early heart disease
…you’re stacking the deck against your heart, especially with daily or heavy use.
What if you already have heart disease?
The American Heart Association’s scientific statement on medical and recreational marijuana is pretty clear: there are no proven cardiovascular benefits of cannabis, and there are multiple potential harms, particularly for people with:
Coronary artery disease
Prior heart attack or stroke
Heart failure
Arrhythmias (like atrial fibrillation)
For these patients, THC-related spikes in heart rate and blood pressure or episodes of reduced blood flow could be enough to tip a vulnerable heart over the edge.
If you have known heart disease and are using cannabis (medically or recreationally), it’s crucial to:
Tell your cardiologist and primary care clinician exactly what you use (route, dose, frequency).
Be especially cautious with high-THC, fast-acting products (concentrates, vapes, high-potency flower).
Watch for new or worsening symptoms: chest pain, shortness of breath, palpitations, dizziness, or neurologic symptoms (sudden weakness, trouble speaking, vision changes).
Practical takeaways if you use cannabis
Treat cannabis like a heart risk factor, not an afterthought.
When you think about your blood pressure, cholesterol, and smoking status, add cannabis use to that same mental list, especially if you use daily or most days.
Daily use is the bigger red flag.
The JAHA study and AHA summary both show a clear step-up in risk with daily use compared to occasional use, and compared to no use.
Smoking is likely the riskiest route but edibles are not off the hook.
If you’re going to use, avoiding smoke and combustion probably lowers some risk, but the UCSF data suggest THC itself can still impair blood vessel function.
If you’re under 50, don’t assume you’re “too young” for cannabis to matter.
The JACC Advances/ACC data showed large increases in heart attack and stroke risk in younger adults who otherwise looked low-risk.
Be honest with your care team.
Your clinicians can’t help you weigh risks if they don’t know you’re using. If a provider brushes it off as “just weed,” it’s okay to say, “I’ve read that daily cannabis use may affect heart risk; can we talk about that?”
Know when to seek urgent care.
Call 911 or go to the ER if you notice: New or severe chest pain or pressure, Sudden shortness of breath, Palpitations with feeling faint, Sudden weakness, numbness, trouble speaking, or vision changes
If you’re thinking about cutting back or stopping, support is available.
About 1 in 3 regular adult cannabis users will meet criteria for cannabis use disorder at some point. If you’ve tried to cut down and can’t, or feel withdrawal (irritability, poor sleep, cravings), talking to a clinician who understands substance use can help you make a plan that fits your life.
Summary: So… can cannabis cause a heart attack?
Here’s the most honest, evidence-based answer we can give right now:
Yes, cannabis appears capable of triggering or contributing to heart attacks and strokes in some people, especially when:
It’s used daily or heavily
It’s smoked
There are underlying risk factors or heart disease
The strongest data show consistent associations with heart attack, stroke, and heart failure, with higher risk at higher levels of use—even after adjusting for tobacco and other factors.
We still need better, prospective studies that follow people over time to prove causation and tease out which products, doses, and patterns of use are most dangerous.
Until then, most major heart organizations have landed in the same place:
Cannabis has no proven cardiovascular benefits, carries real and measurable cardiovascular risks, especially with daily use and smoking, and should be approached with the same caution you’d use for any other substance that stresses the heart.
If you use cannabis and you’re worried about your heart, the next best step is a frank, judgment-free conversation with a clinician who understands both cardiovascular risk and substance use. The goal isn’t to shame you—it’s to help you make informed, realistic decisions about your health.
References
Jeffers AM, Glantz S, Byers AL, Keyhani S. Association of Cannabis Use With Cardiovascular Outcomes Among US Adults. J Am Heart Assoc. 2024;13(5):e030178.
American Heart Association News. Cannabis Use Linked to Increase in Heart Attack and Stroke Risk. Feb 28, 2024.
American College of Cardiology. Cannabis Users Face Substantially Higher Risk of Heart Attack. Press release, Mar 18, 2025.
Mohammadi L, Springer ML, et al. UCSF. Whether It’s Smoking or Edibles, Marijuana Is Bad for Your Heart. Summary of JAMA Cardiology study, May 27, 2025.
Page RL II, et al. Medical Marijuana, Recreational Cannabis, and Cardiovascular Health: A Scientific Statement From the American Heart Association. Circulation. 2020.
