A major new study shows that even light smoking—just a few cigarettes a day—can greatly raise the risk of heart disease and early death.
The risk stays high for many years, even after quitting. These findings come from researchers at the Johns Hopkins Ciccarone Center for Prevention of Cardiovascular Disease and were published in the journal PLOS Medicine.
While it’s been well known that smoking is bad for heart health, this new review offers one of the clearest pictures yet of how harmful even low-level smoking can be. The research team, led by Dr. Michael Blaha, reviewed data from more than 300,000 adults who were followed for up to 20 years across 22 studies.
During that time, over 125,000 people died, and 54,000 experienced serious heart problems like heart attacks, strokes, and heart failure. The study found that people who smoked just two to five cigarettes a day were still 50% more likely to develop heart failure and 60% more likely to die early than people who had never smoked.
One of the most important findings is how long the risks last. Even after quitting, former smokers still had higher chances of heart problems and death compared to those who never smoked. This risk can remain for up to 30 years after quitting.
However, the greatest health benefits happen within the first 10 years after quitting smoking—and the longer a person stays smoke-free, the better.
The study also showed that simply cutting down on smoking isn’t enough. Reducing the number of cigarettes per day does not offer the same level of protection as quitting entirely. That’s why public health experts strongly recommend that smokers quit fully, and as early as possible.
Dr. Blaha and his team emphasized the importance of early action. “Even small amounts of smoking carry serious risks. People need to understand that light or occasional smoking is not safe,” he explained. “The longer someone stays away from cigarettes, the better their heart health and life expectancy will be.”
This large-scale study supports long-standing advice from health organizations: the best way to protect your heart and live longer is to avoid smoking altogether. It also highlights the importance of strong prevention programs to help people quit smoking or never start in the first place.
In short, no amount of smoking is safe. Whether you smoke a pack a day or just a few cigarettes, your heart and health are at risk. But the good news is that quitting at any age can make a big difference—and the sooner, the better.
If you care about heart health, please read studies about top 10 foods for a healthy heart, and how to eat right for heart rhythm disorders.
For more health information, please see recent studies about how to eat your way to cleaner arteries, and salt and heart health: does less really mean more?
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