A major new analysis has found that people who use cannabis may face serious risks to their heart health, including twice the risk of dying from cardiovascular disease. The study, published in the journal Heart, also found increased chances of stroke and sudden heart problems like heart attacks in cannabis users.
Cannabis use has grown rapidly in recent years, especially in places where it’s been legalized or approved for medical use. Many people now see it as safe or even healthy. But researchers warn that this growing popularity may be based on incomplete information, especially when it comes to how cannabis affects the heart and blood vessels.
To get a clearer picture, a group of scientists reviewed data from 24 large studies, covering about 200 million people altogether. These studies looked at the effects of cannabis on serious heart problems. Most of the people in the studies were between 19 and 59 years old, and cannabis users tended to be younger and more often male than non-users.
The results were concerning. People who used cannabis had a 29% higher risk of acute coronary syndrome, which is when blood flow to the heart is suddenly reduced or blocked, often causing a heart attack. They also had a 20% higher risk of stroke. Most alarming of all, cannabis users were found to be twice as likely to die from heart-related causes compared to non-users.
The researchers did note that some of the studies they reviewed had issues, such as not clearly defining how much cannabis was used or not accounting for other risk factors.
Also, because most of the studies were observational, they can’t prove cannabis caused the health problems. However, the researchers still believe their analysis is one of the most thorough so far and gives strong reason for concern.
In a separate opinion piece published with the study, two public health experts—Professor Stanton Glantz and Dr. Lynn Silver from California—argued that it’s time to take the risks of cannabis more seriously.
They say cannabis should be treated like tobacco: not illegal, but strongly discouraged, with rules to protect others from breathing in secondhand smoke or vapor.
They also pointed out that cannabis today is not the same as it was years ago. It’s often much stronger, and it now comes in many forms, such as powerful concentrates, synthetic versions, and food products. These new forms may pose different or greater risks, and more research is needed to understand how they affect the heart.
The experts added that it’s still not clear if the danger comes from the cannabis itself or from other things like the smoke, chemicals in the vapor, or additives in products. They called for clearer health warnings on cannabis products and stronger public education about the risks, just like what is done for cigarettes.
They warned that current rules about cannabis focus too much on legal sales and not enough on protecting health. They believe heart health must become a key part of cannabis policy moving forward.
This large-scale review is one of the most detailed efforts yet to understand how cannabis might harm the heart. While it cannot prove a direct cause-and-effect link, the patterns across millions of people suggest a strong association. The fact that the risk of death from cardiovascular disease is doubled is especially serious and should not be ignored.
Although there are limits to the research—including differences in how cannabis use was measured and potential bias in some studies—the overall message is clear: cannabis is not risk-free, and using it may lead to serious heart problems over time.
As cannabis becomes more widely used, it’s crucial for both the public and policymakers to better understand its risks. People should be aware that cannabis, especially in stronger modern forms, may not be as harmless as once thought—particularly when it comes to heart health.
If you care about heart health, please read studies that vitamin K helps cut heart disease risk by a third, and a year of exercise reversed worrisome heart failure.
For more health information, please see recent studies about supplements that could help prevent heart disease, stroke, and results showing this food ingredient may strongly increase heart disease death risk.
The research findings can be found in Heart.
Copyright © 2025 Knowridge Science Report. All rights reserved.
