Smoking Leaves a Lasting Mark on the Immune System for Years after Quitting

The long term negative impact of smoking on the immune system persists for years after smoking your last cigarette, as was demonstrated by a study of the immune response in 1,000 individuals, published in the scientific journal “Nature.”

This large-scale analysis is part of a broader scientific endeavor to unravel the mysteries behind the vast variations in immune responses among different individuals. The ongoing COVID-19 pandemic has highlighted this diversity, with some individuals experiencing severe illness but others remaining asymptomatic. While factors such as gender, genetics, and age provide partial explanations, the role of other parameters has remained elusive until now.

Led by computational biology expert Violaine Saint-André from the Pasteur Institute in Paris, a team of researchers delved into blood samples and questionnaires collected from 1,000 healthy individuals living in Brittany, France, as part of the Milieu Intérieur consortium. Their findings revealed that, in addition to smoking, high Body Mass Index (BMI) and prior infection with the cytomegalovirus significantly impact the immune system over the long term.

The data concerning smoking were particularly strong, as the impact of smoking on cytokines was as significant as that of age, gender, and genetic background. Moreover, this impact appeared to persist for years after an individual had stopped smoking.

Furthermore, the study highlighted the intricate interplay of individual environmental factors on different cytokines, emphasizing the complexity of tailoring targeted therapies and personalized medicine.

This realization leads to the need for further research and highlights the challenges in explaining the immune system’s intricate workings.