‘Light’ Smokers Still Face Increased Risk of Heart Disease: Study

Adults smoking as few as two cigarettes as day still had an elevated risk of heart disease, researchers found.

A file photo illustration shows a smoker with a pack of cigarettes outside a Sydney office building in Australia, May 5, 2017. Jason Reed/Reuters

People who are “light smokers” still have a higher risk of heart disease and death than people who do not smoke at all, according to a new study published on Nov. 18 by PLOS Medicine.

Adults who smoke two to five cigarettes a day were 50 percent more likely to have cardiovascular disease and 60 percent more likely to die from any cause than people who do not smoke, researchers with Johns Hopkins Ciccarone Center for Prevention of Cardiovascular Disease and other institutions said in the new paper.

The researchers analyzed information from 22 prospective cohort studies within a dataset known as the Cross-Cohort Collaboration Tobacco Working Group. The data comes primarily from the United States. The study had 323,826 adult participants, including 46,125 current smokers and 158,652 former smokers.

The researchers also found that people who smoked 11 to 15 cigarettes a day faced an 87 percent higher risk of cardiovascular disease and were more than twice as likely to have died from any cause than non-smokers.

They also said that quitting smoking immediately decreases risks of health issues such as heart disease, although it can take up to 40 years of not smoking for former smokers to arrive at risk levels similar to never-smokers.

In the United States, smoking has significantly declined in recent decades. Just 11.6 percent of adults smoked in 2022, down from 73 percent in 1965, according to the American Lung Association. Among smokers, the proportion smoking fewer than 15 cigarettes a day has jumped over time.

“In recent years, there has been an increase in the number of people who still smoke, but smoke less. As smoking patterns shift with more people smoking fewer cigarettes, it’s important to understand the cardiovascular risks of low-intensity smoking and the long-term benefits of quitting,” Dr. Michael Blaha of the American Heart Association, one of the authors of the new study, said in a statement.

“We could not clearly answer these questions in the past, but the scope of this study, reflecting more than 320,000 U.S. adults over 20 years, gives us the statistical power to see relationships that other smaller studies cannot.”

American Heart Association President Dr. Stacey Rosen said, “The message here is clear—don’t smoke—and for those who do, quit early in life and strive to quit entirely versus smoking less, because even occasional use of tobacco has substantial health consequences.”

More than 125,000 participants died during the time that was analyzed, the researchers said, including many smokers and former smokers.

The study received funding from the National Institutes of Health and the Food and Drug Administration, as well as the American Heart Association. Several authors reported competing interests, such as funding from Bayer.

Listed limitations included no information on other tobacco products, such as e-cigarettes.