Protect your DNA. Don’t smoke!

Smoking causes so-called epigenetic changes in our DNA, altering the activity of a number of important genes. The consequence is not only an increased risk of a number of serious diseases, but also, in the case of smoking by expectant mothers, a deterioration in the immunity or intellect of their children.

Why does smoking actually increase the risk of lung cancer? This is not only because the organ is clogged with fumes, but also because smoking epigenetically turns off genes that protect lung tissue cells against mutations.

When the researchers exposed lung tissue cells to concentrated cigarette smoke equivalent to one to two packs of cigarettes a day, they found significantly increased levels of the enzyme EZH2, which inhibits gene transcription, after 15 months. This was followed by increased gene methylation, an epigenetic response that can shut down genes completely.

Cigarettes disrupt up to 7,000 genes

Gene methylation is the epigenetic response most affected by smoking. When an international team of scientists compared 16,000 people, they found significantly different patterns of gene methylation in those who smoke or have smoked in the past. For some, these epigenetic marks were evident even 30 years after they had quit smoking.

Smoking has affected the activity of around 7 000 genes in our DNA, including genes linked to various types of cancer, cardiovascular disease, susceptibility to inflammatory processes and even arthritis.

We cannot ignore the fact that smoking-related changes also closely influence the so-called epigenetic age, which is a refinement of the previously used term “biological age”. As the years go by, epigenetic changes in our DNA (especially in the area of gene methylation) increase, which then reflect the actual state of our organism. However, the rate of these changes can be significantly influenced by our lifestyle. Smoking is one of the factors that accelerate epigenetic ageing and with it the ageing of all cells in the body. This is associated with an increased incidence of chronic diseases, as well as a negative cosmetic effect (female smokers have more wrinkles and poorer overall skin quality than non-smokers of the same age).

Affects erections, fertility and the health of offspring

In men, smoking is also associated with erectile dysfunction, but also with reduced sperm quality, which is also due to altered DNA methylation patterns. As a result, smokers have a reduced chance of conceiving offspring and their habit even increases the risk of miscarriage or fetal harm. The negative effect on fertility is also felt by women.

However, the worst effects are caused by smoking during pregnancy, which damages the unborn child in two ways – firstly, by impaired tissue oxygenation and secondly, by increased intensity of negative epigenetic reactions. When researchers looked at the DNA of the newborns of nearly 7,000 female smokers, they found similar DNA changes to those of adult smokers. The authors found differences in a total of 6,073 genes compared to the children of non-smokers.

These genes are linked, for example, to the development of the nervous system and lungs, which explains why children of smokers are more likely to suffer from learning and behavioural disorders or asthma. Epigenetic changes are also the reason why these children are more likely to suffer from cleft lip and palate.

The road to recovery

Of course, the most important change to protect health and slow down ageing is to stop smoking. But the work of repairing the damage does not end there, as years of cigarette smoking have left a number of epigenetic changes to DNA, particularly in the area of increased methylation.

Fortunately, however, epigenetic changes are reversible, so as many lifestyle changes as possible should be made that have a positive epigenetic effect for change. This includes a healthy diet, regular bending, avoiding environmental pollutants and stress.

Dietary supplements containing high concentrations of nutrients or herbs with epigenetic effects can be an effective aid. In particular, we should focus on those that affect the broadest possible spectrum of epigenetic reactions – for example, EGCG, curcumin or pomegranate – or those that are effective in gene methylation – these include omega-3 unsaturated fatty acids and resveratrol.