The harmful effects of tobacco on health and the immune system have already been demonstrated by numerous scientific studies. Indeed, according to Public Health France, “one in three cancers is due to smoking. If the best known is the lung cancerother cancers are also caused by tobacco: throat, mouth, lips, pancreas, kidneys, bladder, uterus”. The immune system’s job is to protect the body against foreign or dangerous invaders such as germs, bacteria, viruses or parasites, explains the MSD Manual. Two types of immunity are distinguished: innate immunity, which is common to all individuals and which corresponds to the body’s immediate response to an attack by pathogens, and adaptive immunity which is acquired. during existence. It takes place slowly and is built from the memory of our body exposed to infectious agents.
In a recent study published in review Nature, researchers from the Pasteur Institute were interested in the impact of cigarettes on the immune response after smoking cessation lasting several years.
Tobacco and the immune system: harmful effects that persist
To carry out their study, the scientists analyzed the immunity of a sample of 1,000 people by carrying out various tests, particularly blood tests. If sex, age, genetic factors and body mass index are well-known risk factors for immune defense, scientists discovered in this study that tobacco was an additional risk factor. Indeed, analyzes have shown that smoking influences innate and adaptive immune responses. However, its effect on innate responses disappears quickly after stopping smoking, while its effect on adaptive responses persists long after smoking cessation. Thus, adaptive immunity remains damaged for years after having stop smoking.
According to Dr Yang Luo, an immunologist at the University of Oxford (UK) who spoke in a press release,“This highlights the importance of considering not only the immediate effects, but also the lasting consequences of lifestyle choices such as smoking on the immune system.” Researchers from the Pasteur Institute emphasize that this effect of tobacco on the immune system is linked to epigenetics. As Inserm explains, “Epigenetics corresponds to the study of changes in gene activity, which do not involve modification of the DNA sequence and which can be transmitted during cell divisions”. More simply, tobacco consumption would affect the way in which certain genes interact.
Quitting cigarettes remains very beneficial
However, stopping smoking still presents very rapid health benefits, this is what tobacco specialist Marion Adler underlined when interviewed by France Info. According to her, “this study is interesting, because it once again shows the toxicity of tobacco, and its effects on immunity”. Furthermore, it should be kept in mind that after stopping smoking, “Some of that immunity comes back and is quite effective.” The expert explains that she wants to give a positive message to smokers, reminding them that there is “an immediate benefit from stopping smoking, for example with carbon monoxide which disappears within 24 hours”.
Sources:
- Smoking changes adaptive immunity with persistent effects – Nature – February 14, 2024
- Smoking scars the immune system for years after quitting -Nature – February 14, 2024
- Overview of the Immune System – MSD Manual
- Epigenetics: a genome, full of possibilities! – Inserm