A major new review published on June 17 in the medical journal Heart has raised alarms about the cardiovascular risks of marijuana, suggesting it may pose a greater threat for heart attack, stroke, and cardiovascular death than other illicit drugs like cocaine and opioids. The findings, drawn from an analysis of 24 studies involving nearly 200 million people, challenge the perception of cannabis as a relatively benign substance and underscore the need for heightened public health awareness as its use grows in the United States and globally.
The study, led by researchers at the University of Toulouse, France, found that cannabis users face a 29% higher risk of acute coronary syndrome—conditions like heart attack caused by reduced blood flow to the heart—compared to non-users. They also have a 20% increased risk of stroke and a doubled risk of dying from cardiovascular disease. One striking finding, based on a French hospital database, indicated that cannabis was a stronger predictor of heart attack than cocaine or opioids, particularly among younger patients without pre-existing heart conditions. “This study is a wake-up call,” said Dr. Emilie Jouanjus, the lead researcher. “The cardiovascular risks of cannabis are underestimated, and we need to approach it with the same caution as tobacco.”
The review comes at a time when marijuana legalization is expanding across the U.S., with 24 states and the District of Columbia allowing recreational use and 38 states permitting medical cannabis as of 2025. Recreational, medicinal, and sacramental use of marijuana is legal in the U.S. Virgin Islands, following the signing of legislation by Governor Albert Bryan Jr. in January 2023. The Office of Cannabis Regulation has since been working to implement rules to govern the emerging industry.
The increasing potency of marijuana, with tetrahydrocannabinol (THC) levels rising from 4% in the 1990s to over 15% in modern strains, may amplify these risks, the researchers noted. Smoking, the most common method of consumption in the studies, delivers THC and other compounds directly into the bloodstream, potentially triggering heart rhythm disturbances or blood vessel constriction.
The analysis, which included data from 2016 to 2023 and focused on adults aged 19 to 59, drew from diverse sources, including hospital records and population surveys. A 2024 study cited in the review found that daily cannabis users had a 25% higher risk of heart attack and a 42% higher risk of stroke compared to non-users. In contrast, cocaine, known for its acute cardiovascular effects like heart attacks and arrhythmias due to its stimulant properties, appeared less predictive of these outcomes in some datasets, possibly due to its lower prevalence of use compared to cannabis.
Despite its robust sample size, the review has limitations that temper its conclusions. Many studies relied on self-reported cannabis use, which can be inconsistent, and exposure measurements were often imprecise, failing to account for frequency, dosage, or method of consumption. Most data focused on smoking, leaving the risks of edibles, vaping, or other forms unclear. “There’s a lot we don’t know about how cannabis affects the heart long-term,” said Dr. Robert Kloner, chief science officer at Huntington Medical Research Institutes, who was not involved in the study. “We need more research on mechanisms—how THC interacts with blood vessels or triggers inflammation.”
The comparison to cocaine and opioids also warrants caution. Cocaine’s acute effects, such as rapid heart rate and blood pressure spikes, are well-documented, but its lower usage rate—about 2% of U.S. adults in 2023 compared to 18% for cannabis—may skew comparative risk assessments. Opioids, while linked to overdose deaths, have less direct cardiovascular impact, making marijuana's relative risk appear higher in certain contexts.
The findings have sparked calls for action among health experts. The American Heart Association, which funded part of the research, urged clinicians to screen patients for cannabis use, particularly those with heart conditions or risk factors like diabetes or hypertension. “We need to treat cannabis like tobacco in our public health messaging,” said Dr. Rose Marie Robertson, AHA’s deputy chief science officer. “It’s not about criminalizing use but about informing people of the risks.”
Public health campaigns face challenges in balancing these warnings with the realities of legalization. Cannabis use has surged, with 50.4 million Americans reporting past-year use in 2023, according to the National Institute on Drug Abuse.
Researchers are also exploring how THC, the psychoactive component of cannabis, may disrupt heart rhythm or cause inflammation, and whether non-psychoactive components like CBD pose similar risks. “The potency of today’s cannabis is a new variable,” Jouanjus said. “We’re not dealing with the same drug studied decades ago.”
