Smoking's Impact on the Immune System Can Last for Years After Quitting, New Study Says

Mar. 15, 2025

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Smoking cigarettes can have years-long impacts on the immune system, according to anew study.

Earlier this week, a study published in the journal Nature highlighted how smoking tobacco can drastically change a person’s immune system, alongside other common effects that were previously known.

Per the study, smoking makes it harder for the body to fight off infection immediately, as well as over time. The findings added that tobacco use can also create a higher risk for individuals to develop chronic diseases, including rheumatoid arthritis and lupus.

“Stop smoking as soon as possible,” study coauthor Dr. Violaine Saint-André, a specialist in computational biology at Institut Pasteur in Paris, said in a statement toCNN. “The key message of our study, especially to the youth, is that there seems to be a significant interest for long-term immunity to never start smoking.”

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In order to come to the conclusions discovered, researchers part of the study monitored blood samples from 1,000 healthy individuals, both men and women, who were between the ages of 20 to 69.

Wanting to discover how over 100 variables — including lifestyle, socioeconomic issues, dietary habits, age, sex and genetics — affected immune response, the researchers exposed the blood to various ailments.

The study noted that even when smokers who took part in the study quit, their immune systems improved, though they did not recover till many years later. The more an individual smoked, the more their immune system changed, the study added.

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Currently, cigarette smoking remains the leading cause of preventable disease and death in the United States, according to theCenters for Disease Control and Prevention (CDC).

The act kills more than 480,000 Americans each year, per the organization, and an estimated 11.5% of adults across the nation were cigarette smokers in 2021.

source: people.com