Key points from article :
A major new analysis led by Michael Blaha, and published in PLOS Medicine, reinforces a clear conclusion: even smoking a few cigarettes a day carries significant cardiovascular risk, and quitting entirely is the only reliable way to protect long-term health. The research, funded by the National Heart, Lung, and Blood Institute and the U.S. Food and Drug Administration, builds on decades of evidence showing that smoking is the leading preventable cause of disease and death in the United States.
The Johns Hopkins–led team combined data from 22 long-term population studies, covering more than 323,000 adults followed for up to two decades. With over 125,000 deaths and 54,000 cardiovascular events recorded, the dataset allowed researchers to examine how smoking intensity, lifetime exposure, and years since quitting each influence the risk of heart disease and mortality. Participants ranged widely in smoking history: 14% were current smokers, nearly half were former smokers, and just over a third had never smoked.
Using advanced statistical models, the researchers found that any level of smoking—including just a few cigarettes daily—substantially increases the risk of cardiovascular disease and premature death. Cutting down helps, but does not eliminate risk. The strongest protective factor was time since quitting, underscoring the importance of stopping smoking as early as possible.
The study provides some of the most detailed estimates yet of how smoking habits shape heart health, offering policymakers and clinicians clearer evidence to guide public health messaging. As corresponding author Michael Blaha, M.D., M.P.H., notes, the findings highlight a simple truth: reducing cigarette use isn’t enough—quitting completely is the best path to a healthier, longer life.
