Regular marijuana use—smoked or eaten—can cause serious cardiovascular harm, according to UCSF researchers, challenging the myth of pot’s safety as legalization spreads.
At a Glance
- Long-term cannabis use—smoked or ingested—linked to serious cardiovascular risks
- UCSF study found blood vessel function cut by about 50% in regular users
- Participants showed signs of endothelial dysfunction, linked to heart attacks and hypertension
- Both smoking and edibles impaired vascular health through distinct biological mechanisms
- Study raises alarms as marijuana legalization accelerates nationwide
Pot’s Hidden Damage to Your Cardiovascular System
As marijuana legalization expands across the United States, new research from the University of California San Francisco warns that cannabis may pose serious risks to your heart. In a study published in JAMA Cardiology, UCSF scientists report that chronic marijuana use—whether smoked or consumed in edibles—leads to significantly impaired blood vessel function, mirroring the damage caused by tobacco use.
Watch a report: Marijuana’s Surprising Cardiovascular Dangers.
The research, which involved 55 regular users from the Bay Area, found that cannabis users had roughly 50% reduced vascular function compared to non-users. These effects were consistent across users of both smoked and edible THC, undermining the common perception that edibles are safer alternatives. The participants, despite being young and seemingly healthy, displayed vascular symptoms typically associated with aging smokers or those at risk for heart disease.
Different Methods, Same Cardiac Risk
The study found that both groups of users—smokers and edible consumers—suffered from endothelial dysfunction, a condition where blood vessels fail to dilate properly. This dysfunction is a red flag for potential heart attacks, high blood pressure, and stroke. While smokers’ blood serum showed harmful biochemical changes, those same markers weren’t present in edible users. Still, both delivery methods led to equivalent cardiovascular damage.
Lead author Leila Mohammadi, MD, PhD, noted, “These results suggest smoking marijuana negatively affects vascular function for different reasons than ingesting THC does.” This suggests that the method of consumption alters how the damage occurs—but not the fact that it does.
Ignored Risks in the Legalization Push
As marijuana becomes legal for recreational use in 24 states, policymakers are often quick to highlight economic benefits and criminal justice reforms. But this new research urges caution. Dr. Bradley Serwer, commenting on the findings, emphasized, “We have known that the chronic use of THC-containing compounds can have negative health consequences — this study just reaffirms those prior studies.”
The study’s authors, backed by institutions including the National Institute on Drug Abuse and California’s Department of Cannabis Control, made clear their findings are not an ideological rebuke but a scientific reality check. As Dr. Serwer concluded, “The decision to use or avoid [cannabis] should be made with all benefits and risks in mind.”
The UCSF study is not the final word, but it forces a new conversation about public health and cannabis policy. The findings underscore the need for further investigation—and possibly more regulation—before declaring cannabis a completely safe alternative to alcohol or tobacco.
