A new study raises serious concerns about cannabis and heart health. Research led by investigators at UCSF and published in JAMA Cardiology shows that cannabis use—whether smoked or consumed as edibles—may impair cardiovascular function. The findings challenge the idea that cannabis is a safer alternative to tobacco, especially as legalization and consumer use expand globally, including in Thailand.
For Thai readers, the study arrives at a moment when policy, health messaging, and potential economic benefits of cannabis are hotly debated. Thailand has moved to legalize certain cannabis activities, creating a local landscape where public health guidance needs to keep pace with evolving regulations. The new evidence underscores the importance of clear information for patients, clinicians, and regulators.
In the study, 55 participants were divided into regular cannabis users and non-users with no nicotine history. Regular users consumed cannabis at least three times weekly for a year or longer; smoking users averaged about a decade of use, while those who ate edibles averaged around five years. Both smoking and edible cannabis users showed markedly reduced vascular function compared with non-users. On average, blood vessel performance in users was about half of that in non-users, indicating a meaningful risk of endothelial dysfunction, the condition in which the lining of blood vessels does not regulate flow effectively.
Endothelial dysfunction can lead to higher blood pressure and a greater likelihood of heart disease, stroke, and related conditions. The study aligns with earlier work linking marijuana to rhythm disturbances and cardiovascular events, while adding new detail about how different forms of cannabis may impact the body. Researchers note that the adverse effects are not limited to smoked cannabis; even non-smoked forms appear to affect heart and blood vessel health, likely through direct interactions with heart and vascular receptors.
Experts emphasize caution and the need for ongoing research. A senior investigator at UCSF remarked that cannabis use in any form should not be viewed as harmless for the cardiovascular system. Cardiovascular scientists also highlight the importance of regular medical checkups and open discussions with health professionals, particularly for habitual users or individuals with a family history of heart disease.
The Thai context adds another layer of urgency. Thailand is pursuing a broader approach to herbal wellness and medical cannabis, which has expanded in recent years. Public health messaging, regulation, and consumer education must address real risks to heart health, not only the potential benefits. Medical associations and university hospitals in Bangkok and other cities have called for more robust, long-term data on the effects of cannabis—especially products like edibles and vapes that are popular in local markets—so users can make safer choices.
In Thai communities, there is ongoing confusion about the relative safety of smokeless cannabis products. This misperception can be dangerous if people assume edibles or vapes are risk-free. Public health officials should pair regulatory measures with accessible, science-based warnings and clear labeling about potency and dosage. A balanced approach is needed to support both legitimate medical use and consumer protection.
Looking ahead, researchers acknowledge many questions remain. The precise ways THC and other compounds damage blood vessels are not fully understood, and it is not clear whether occasional use carries the same risks as regular, high-dose use. Individual differences in genetics, diet, and health status may influence risk levels. Policymakers and health authorities should consider population studies in Thailand to understand how legalization and commercialization affect rates of heart disease, stroke, and hypertension. Integrating cardiovascular risk screening into routine care and monitoring cannabis use in the population are sensible next steps.
Despite the economic and therapeutic interest surrounding cannabis in Thailand, science should guide public health decisions. For current users, regular medical consultation is important, particularly for those with hypertension or a family history of heart disease. Health authorities can support safer choices through targeted education campaigns, thoughtful product labeling, and keeping regulations aligned with the latest scientific findings.
Bottom line: there is no form of cannabis use that is truly heart-safe. Thai readers weighing cannabis use for wellness, traditional healing, or recreation should consider the medical risks, have open conversations with clinicians, and stay informed about new research.
For further context, a range of international findings highlight the cardiovascular considerations of cannabis. Data from leading health institutions and research bodies emphasizes cautious use and ongoing study to better understand long-term effects on heart and blood vessels.