Cancer And Smoking

What is cancer?

Cancer is the irregular growth and proliferation of dysfunctional cells in any tissue and/or organ in the human body. Cancer cells can spread throughout the body via the blood and lymphatic systems.1 

Cancer comes in more than a hundred distinct varieties. For the most part, cancers are referred to by the organ or cell type in which they first manifest. For instance, lung cancer starts in the lungs, while laryngeal cancer starts in the larynx (voice box).

Smoking is a significant cancer risk factor 

Cancer can develop in essentially any part of the body exposed to cigarette smoke. Smoking can cause cancers of the oral cavity and pharynx, digestive tract, large and small intestines, liver, pancreas, bronchi, ureters, bladder, cervix, kidneys, and pelvic lining, including acute myeloid leukaemia.2 

Cigarette smoking is the leading cause of lung cancer as it contains more than 7,000 toxic chemicals, which are known to be carcinogenic to humans or animals.3 Cigarette smokers are 15 to 30 times more likely to develop lung cancer or die from lung cancer than nonsmokers.

Chemicals in cigarettes cause DNA damage 

Cigarette smoke contains many chemicals, some of which are known or suspected carcinogens. These include nicotine, formaldehyde, ammonia, carbon monoxide, carbon dioxide, benzopyrenes, tar, acetone, hydroxyquinone, cadmium, and nitrogen oxides. Epithelial cells in the larynx, bronchi, and lungs are directly exposed to at least 60 potent chemical carcinogens when a person smokes.4 

Chronic inflammation is thought to be one of the main effects of smoking which causes mutations or DNA damage and inflammatory reaction. This causes more cells to grow uncontrollably in the exposed epithelial area, making it easier for cells to change/mutate, which eventually leads to cancer cells.5

Smoking weakens the immune system

Immune cells normally take care of cells with irreparable DNA damage. Some of the most significant immunologic changes and immunosuppressive effects on the innate immune response are seen in people who regularly use tobacco products, which have high concentrations of tar and nicotine.6 

Cigarette smoke inhibits chemotaxis, kinesis, and cell signalling and reduces the phagocytic activity of neutrophils. Additionally, it inhibits the release of reactive oxygen species (ROS), thereby interrupting the killing of pathogens by neutrophils and other innate immune cells.6

Tips for quitting smoking

Cravings for tobacco or the desire to smoke can be intense for most people who use tobacco. However, you have the power to resist these urges. 

Find motivation to quit

You will need a strong, personal incentive to break the habit. It could be to keep your loved ones safe from secondhand smoke. Or reduce your vulnerability to diseases like lung cancer, cardiovascular disease, and others.


Nicotine has a profound effect on the brain. An addiction like smoking is very difficult to break. Speak to your doctor about all the options available to you, including classes, mobile apps, counselling, medication, and hypnosis, to help you kick the habit. 

Nicotine Replacement Therapy

Short-acting nicotine replacement therapies like gum, lozenges, nasal sprays, and inhalers can help you overcome intense cravings. They are safe to use along with long-acting nicotine patches or non-nicotine stop-smoking drugs.

Avoid triggers

Parties, bars, stressful times, and coffee are likely to trigger tobacco urges. Find your triggers and plan to avoid or overcome them without tobacco. 

Physical activity

Exercise can help you avoid tobacco cravings. Running up and down the stairs a few times can satisfy a tobacco craving. If you do not like exercise, you can sew, work with wood, or keep a journal. If you need a diversion, you could clean the house or organise your paperwork.

Relaxation techniques

Stress is a major motivator for taking up smoking. It can be stressful trying to resist a tobacco craving. Try deep breathing, muscle relaxation, yoga, visualisation, massages, or listening to calming music to help alleviate stress.

Call for help

If you need help overcoming a tobacco craving, talk to a loved one, friend, or member of a support group. They can help you resist the urge to smoke and keep going. Counselling services, such as behavioural therapy, can aid smokers in developing and maintaining a plan to quit smoking. 

Healthy Diet

Studies suggest that cigarette smokers tend to have lower levels of vitamin C and B vitamins in their bloodstream.7 B vitamins, often referred to as "anti-stress vitamins", are useful for maintaining mental equilibrium. Also, to some extent, vitamin C's antioxidant properties may shield the lungs from the oxidative stress that tobacco smoke causes.8 These vitamins may be helpful in easing the withdrawal symptoms associated with quitting smoking, but they will not actually cause the user to stop smoking.


Cigarette smoking is a leading cause of cancer growth in many organ systems. Cigarette smoke contains toxins that can suppress the immune system, alter the DNA of cells, and make it more difficult to eliminate cancerous growths. This results in the uncontrollable growth of precancerous cells, which ultimately leads to the development of tumours. The best way to protect yourself from developing cancer is to never start smoking or to give up the habit once you have started. On a similar note, avoiding exposure to second-hand smoke is important. Doctors can prescribe medications to help with cravings, while mobile apps and behavioural adjustments can help with motivation. You can get nicotine patches and other aids to help you kick the habit from the comfort of your own home. However, a consultation with a medical professional should be your first step.


  1. Cancer [Internet]. [cited 2022 Oct 17]. Available from:
  2. CDCTobaccoFree. Smoking and cancer [Internet]. Centers for Disease Control and Prevention. 2022 [cited 2022 Oct 17]. Available from:
  3. What Are the Risk Factors for Lung Cancer? [Internet]. 2021 [cited 2022 Oct 17]. Available from:
  4. Hecht SS. Tobacco carcinogens, their biomarkers and tobacco-induced cancer. Nat Rev Cancer. 2003 Oct;3(10):733–44.
  5. Alexandrov LB, Ju YS, Haase K, Van Loo P, Martincorena I, Nik-Zainal S, et al. Mutational signatures associated with tobacco smoking in human cancer. Science. 2016 Nov 4;354(6312):618–22.
  6. Yamaguchi NH. Smoking, immunity, and DNA damage. Transl Lung Cancer Res. 2019 May;8(Suppl 1):S3–6.
  7. Vardavas CI, Linardakis MK, Hatzis CM, Malliaraki N, Saris WH, Kafatos AG. Smoking status in relation to serum folate and dietary vitamin intake. Tob Induc Dis. 2008 Sep 9;4:8.
  8. Luo J, Shen L, Zheng D. Association between vitamin C intake and lung cancer: a dose-response meta-analysis. Sci Rep. 2014 Aug 22;4:6161.

Avantika Pandey

General Dentist • Public Health Specialist, University of York, UK

I am a healthcare researcher with a background in dentistry who is presently pursuing a Master of Public Health at the University of York, UK. Prior three years' experience collaborating with medical teams and health care professionals to deliver medical treatment and patient care in clinics and hospitals.
I am a member of The Global Mental Health and Cultural Psychiatry Research Group, which promotes mental health care in LMIC. I am also working under the IMPACT program under University of York for mental health care in LMIC. presents all health information in line with our terms and conditions. It is essential to understand that the medical information available on our platform is not intended to substitute the relationship between a patient and their physician or doctor, as well as any medical guidance they offer. Always consult with a healthcare professional before making any decisions based on the information found on our website.
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