Smoking, the facts


  • Tobacco is the leading global cause of preventable illness and death.
  • Smoking is the leading cause of lung cancer worldwide
  • Smoking accounts for 13% of the cancer cases diagnosed each year in Ireland.
  • Smoking is also responsible for other cancer diagnoses part from lung cancer such as mouth, head and neck, breast cancer, bladder cancer and kidney cancer. 
  • The National Cancer Registry of Ireland predict that by 2035, over 4,700 cases of cancer diagnosed will be attributed to smoking. To reduces your risk, it is advised that you don’t smoke, and if you do, to quit.

Who smokes in Ireland?

According to the Healthy Ireland Survey 2021

  • 18% of the population are currently smokers - 16% smoke daily and 2% smoke occasionally.
  • Smoking rates are highest among those aged 25 to 34. 20% of this age group are currently smokers.
  • Men are more likely to smoke than women. 19% of men are current smokers, compared to 16% of women.
  • 4% of the population have used e-cigarettes, with those aged under 25 most likely to have used them


However, there is some good news:

  • 44% of all who smoked in the last 12 months have attempted to quit
  • 27% of those who attempted to quit in the last 12 months were successful

Smoking kills

Tobacco is the leading global cause of preventable illness and death. Of all cancer diagnoses in 2016, 1 in 8 could be linked back to smoking.

Tobacco is the major cause of cancer accounting for 90% of lung cancer diagnosis worldwide. Smoking is the most harmful form of tobacco use and causes the heaviest burden of tobacco-related illness.

One in every two smokers will die of a tobacco-related disease. These diseases include a wide range of cancers, as well as respiratory and cardiovascular diseases. Smokers are more likely to get cancer than non-smokers. This is particularly true of lung cancer one of Ireland’s most common cancers, as well as throat cancer and mouth cancer.

Data from the Department of Health suggests that every six and a half seconds, someone in the world dies from a tobacco related illness. This equates to 1.5 million people every year

Tobacco was responsible for more than 100 million deaths worldwide in the 20th century. The World Health Organization has estimated that, if current trends continue, tobacco could cause a billion deaths in the 21st century.

Tobacco and lung cancer

Tobacco use is the leading cause of cancer yet, it is avoidable. There is no safe way to use tobacco, but smoking is the most dangerous. This is because the greatest cancer risk comes from the combustion of tobacco or tobacco smoke. Most toxic substances including carcinogens (cancer causing chemicals) are created during the burning process.

Tobacco causes different types of cancer, especially if smoked. Tobacco smoke also causes cancer in non-smokers who inhale tobacco smoke from smokers. This is known as second hand or passive smoke. 

The risk increases with:

  • The more years you smoke
  • The more cigarettes you smoke each day
  • The younger you are when you start smoking.

Each cigarette you smoke takes five and a half minutes off your life, and overall takes 10 to 15 quality years off your life. The best way to reduce your risk is the quit now. 

Nicotine addiction

Smoking is very addictive because tobacco contains nicotine, which is a powerful drug. Cigarettes are deliberately designed to give you a fast nicotine hit. It takes less than 20 seconds for the drug to reach your brain from inhaled cigarette smoke.

Nicotine causes addiction in much the same way as heroin or cocaine. It is just as addictive as these ‘harder’ drugs.

The addictive nature of nicotine is why most smokers say they want to quit but find it so difficult. If you start smoking, you may find it very hard to stop later on and over 83% of smokers say they wish they had never taken up smoking.

How does smoking cause cancer?

The main way that smoking causes cancer is by damaging our DNA. When these cells are damaged, including key genes that protect us against cancer, they can be difficult to repair, therefor leaving our bodies more open to illness and the development of cancer.

Many of the chemicals found in cigarettes have been shown to cause DNA damage, including benzene, polonium-210, benzo(a)pyrene and nitrosamines.

This is already bad news, but it’s made worse by other chemicals in cigarettes. For example, chromium makes poisons like benzo(a)pyrene stick more strongly to DNA, increasing the chances of serious damage.

And chemicals like arsenic and nickel interfere with pathways for repairing damaged DNA. This makes it even more likely that damaged cells will eventually turn cancerous.

Chemicals in cigarette smoke enter our blood stream and then can affect the entire body. This is why smoking can contribute to so many different diseases, including:

  • At least 14 types of cancer
  • Heart disease
  • Various lung diseases

How long does it take for smoking to cause cancer?

It usually takes many years, or decades, for the DNA damage from smoking to cause cancer. Our bodies are designed to deal with a bit of damage, but it’s hard for the body to cope with the number of harmful chemicals in tobacco smoke.

Each cigarette can damage DNA in cells, but it is the build-up of damage in the same cell that can lead to cancer. However, research shows that for every 15 cigarettes smoked, there is a DNA change which could cause a cell to become cancerous. This is why it’s better to give up smoking sooner rather than later.

How does smoking weaken the body’s defences?

Smokers are also less able to handle toxic chemicals than those with healthy lungs and blood due to their cell’s weakened state.

We all have special ‘cleaner’ proteins called ‘detoxification enzymes’ that mop up harmful chemicals and convert them into harmless ones. But the chemicals in smoke, such as cadmium, can overwhelm these cleaners.

Other chemicals like formaldehyde and acrolein kill cilia, the small hairs that clean toxins from your airways.

Cigarette smoke also impacts the immune system – increasing the number of cells which can encourage tumour growth in the lungs and suppressing the ones that kill cancer cells.

For more information on how smoking impacts your risk of lung cancer click here

For helpful tips on how to quit smoking and reduce your cancer risk, click here

What about E-Cigarettes?

  • Electronic cigarettes (e-cigarettes) are battery-powered devices. They heat nicotine mixed with flavourings and other chemicals to create an aerosol that the user inhales
  • 3% of the Irish population use e-cigarettes
  • Usage is highest among those aged under 25
  • Most adults who vape also smoke cigarettes or used to smoke cigarettes
  • Vaping may be less harmful than cigarettes but vaping is not harm-free!
  • The WHO states that there is evidence that e- cigarettes are harmful to health especially when used by children and adolescents
  • A study by Queen's University Belfast showed that there is little difference between the effect of cigarette smoke and e-cigarette vapour on lung bacteria. Both increase the risk of chronic damage to the lungs (COPD)
  • Further research is necessary to study the long-term impact of using E-cigarettes

Tobacco-Free-Ireland-–-time-for-Tobacco-21.pdf (