15th March 2021 – by Paz García

The immune system of quitters is almost completely restored to a healthy state, according to the latest research from TwinsUK in collaboration with the Italian Institute for Genomic Medicine and the University of Turin.

Smoking kills more than 8 million people every year across the world and is linked to a range of diseases, including several types of cancer.

This study is the first to show the effect of smoking on specific cell types, building on previous evidence that smoking impacts the overall levels of key immune system cells.

First author Giulia Piaggeschi from the Italian Institute for Genomic Medicine and the University of Turin said:

“We’ve known for a long time that smoking is bad for your health. The good news from this study, however, is that by stopping smoking, your immune system cells are almost completely restored back to normal.”

The team carried out a detailed analysis of the immune system cells in 358 healthy women from TwinsUK, some of whom were smokers while others had never smoked or were ex-smokers.

The researchers found that smokers had lower levels of certain protective immune cells and higher levels of immune cells that cause chronic inflammation.

Individuals who had quit smoking however had immune cells levels back to normal, with the exception of only two specific types which remained altered.

On the findings, senior author Dr Alessia Visconti from TwinsUK, King’s College London, said:

“We now need further research to understand how these changes in immune cells may be linked with smoking- and immune-related diseases such as cancer and autoimmune conditions.”

Piaggeschi et al. (2021) Immune trait shifts in association with tobacco smoking: a study in healthy women. Front. Immunol.