Damage to the immune system from smoking appears to linger even years after a former smoker took that last puff.
Researchers studied the immune responses of 1,000 healthy people ages 20 to 69 for the study, published this week in the journal Nature. It was part of a larger effort to figure out why people have such different immune responses.
While the risk of developing lung cancer, heart attack or stroke related to smoking is by now well established, the new research finds smoking lessens the body’s ability to fight infections and may contribute to chronic inflammatory diseases like rheumatoid arthritis and lupus.
“Stop smoking as soon as possible,” said study co-author Violaine Saint-André, who specializes in computational biology at Institut Pasteur in Paris, quoted by CNN. “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.”
According to Nature.com, “In addition to cigarette smoking, the study found that having a higher-than-average body mass index and having previously been infected with a typically benign virus called cytomegalovirus also affect the immune response.”
Study nuts and bolts
The researchers examined 136 different factors to see how they impacted immune response, ranging from lifestyle and socioeconomics to diet and genetics, among others.
They took blood samples from the participants and then measured the samples’ response to different common bacteria and viruses, including the flu. The researchers noted that the response could be somewhat different within the body.