A sweeping review published today in Nature Reviews Cardiology concludes that nicotine is harmful to cardiovascular health regardless of how it is consumed—whether through traditional cigarettes, chewing tobacco, e-cigarettes, or nicotine pouches. The findings challenge the notion that newer nicotine products are safe for the heart, even as they eliminate the smoke and combustion associated with conventional smoking.
The review, led by Thomas Münzel of the University Medical Centre Mainz in Germany, does not equate all nicotine products. Conventional cigarettes and waterpipes remain the most dangerous, largely due to the toxic byproducts of combustion. But the authors argue that moving away from smoke does not eliminate cardiovascular risk—it merely reduces it along a spectrum they call the “cardiovascular continuum of harm.”
At the top of this continuum sit combustible products, followed by heated-tobacco devices, e-cigarettes, and oral nicotine products such as chewing tobacco and pouches. The clear implication: while eliminating smoke lowers harm, only eliminating nicotine altogether removes the nicotine-related cardiovascular risk.
Nicotine’s double hit on blood vessels
The researchers traced the biological pathways through which nicotine damages the cardiovascular system, identifying two distinct mechanisms. First, nicotine disrupts the endothelium—the thin layer of cells lining blood vessels—by suppressing prostacyclin, a vasodilator, while boosting endothelin-1, a potent constrictor. Second, it acts directly on vascular smooth muscle cells, interfering with potassium channels and calcium regulation to promote constriction even when the endothelium is intact.
Beyond these direct effects, the review highlights oxidative stress, arterial stiffness, and inflammation as common consequences of nicotine exposure. Endothelial dysfunction, they argue, serves as an early marker of cardiovascular damage, setting the stage for atherosclerosis, hypertension, and heart failure.
“It is apparent that nicotine is an active driver of endothelial dysfunction, the earliest step on the path to atherosclerosis, hypertension and heart failure—and only abstinence is risk free,” said co-author Filippo Crea.
“E-cigarettes and heat-not-burn devices were initially marketed as reduced-risk alternatives to combustible cigarettes, but our data show these products sit on a continuum of cardiovascular risk, not off it,” said Thomas Münzel. “Removing combustion clearly reduces harm—but it does not remove it.”
The review arrives as the European Union prepares to overhaul its tobacco-control framework, with Brussels grappling with declining cigarette use alongside the rapid rise of e-cigarettes, heated tobacco, and nicotine pouches. The EU’s proposed tax overhaul aims to address these novel products, but the authors argue for a more fundamental shift.
“Nicotine’s cardiovascular toxicity at the molecular level, combined with its well-documented, high dependence-forming potential make the case for a coherent, nicotine-based regulatory framework rather than the current patchwork of product-specific rules,” said Münzel.
The findings add to a growing body of evidence that nicotine is not a benign stimulant. For policymakers in Berlin, Paris, and other capitals, the message is clear: harm reduction through smoke-free products is not the same as risk elimination. As the EU debates its next steps, including taxing vaping, the review underscores the need for a unified approach that treats all nicotine products with caution.
For the public, the takeaway is straightforward: if you care about your heart, the safest choice is to avoid nicotine altogether. While switching from cigarettes to e-cigarettes may reduce some harms, it does not make the heart safe.
