Smoking and Cancer: Unmasking the Deadly Link

Cigarette smoking has long been associated with a range of serious health problems, but among its most devastating consequences is its strong link to cancer. Despite decades of public health campaigns and warning labels, smoking remains a leading cause of preventable cancer deaths worldwide. This blog explores the relationship between smoking and cancer, the science behind it, and why quitting smoking is one of the most important steps toward a healthier life.

The Dangerous Chemistry of Cigarettes

Cigarettes contain over 7,000 chemicals, and at least 70 of them are known to cause cancer (carcinogens). These include:

• Tar – a sticky substance that coats the lungs and contains numerous carcinogens.
• Formaldehyde – used in embalming fluid, also a known carcinogen.
• Benzene – found in gasoline, linked to leukaemia.
• Polonium-210 – a radioactive element.
• Arsenic – used in pesticides.

When inhaled, these chemicals damage the DNA in our cells, disrupting their normal function and triggering uncontrolled growth—the hallmark of cancer.

Types of Cancer Caused by Smoking

Smoking doesn’t just affect the lungs. It increases the risk of developing cancers in multiple organs, including:

• Lung cancer – responsible for about 85% of all cases in smokers.
• Throat and mouth cancers – including the larynx, tongue, and oesophagus.
• Bladder cancer – carcinogens in tobacco are filtered by the kidneys and stored in the bladder.
• Pancreatic cancer – among the deadliest forms.
• Kidney, liver, and stomach cancers – also strongly linked to tobacco use.
• Cervical cancer – smoking weakens the immune system, making the body less effective at fighting HPV infections, a key cause of cervical cancer.
• Acute myeloid leukaemia (AML) – a cancer of the blood and bone marrow.

In fact, smoking is linked to at least 14 different types of cancer.

Secondhand Smoke: A Silent Killer

You don’t have to be a smoker to be at risk. Secondhand smoke—the smoke from a burning cigarette and from the smoker’s breath—also causes cancer. Children and non-smoking adults exposed to secondhand smoke are at higher risk for:

• Lung cancer
• Heart disease
• Respiratory illnesses

This makes smoking not just a personal health issue, but a public health concern.

The Good News: Quitting Helps—At Any Age

The moment you quit smoking, your body begins to heal:

• After 1 year: Your risk of coronary heart disease drops by 50%.
• After 5 years: Risk of mouth, throat, oesophagus, and bladder cancer is cut in half.
• After 10 years: Lung cancer death rate is about half that of a continuing smoker.
• After 15 years: Your risk of heart disease is the same as someone who never smoked.

Quitting smoking reduces your risk of cancer—no matter how long you’ve smoked.

How to Quit Smoking

Quitting smoking is hard, but not impossible. Here are some effective strategies:

• Nicotine replacement therapy (NRT): Patches, gum, lozenges.
• Prescription medications: Like varenicline (Chantix) or bupropion (Zyban).
• Behavioural support: Counselling, support groups, quitlines.
• Mobile apps and online resources: Many free programs are available.

Talking to a doctor can help tailor a quit plan that works for you.

Final Thoughts

Smoking is a major risk factor for cancer, but the good news is that it's a risk you can control. By quitting smoking, you can significantly reduce your chances of developing cancer and improve your overall quality of life. Whether you're a long-time smoker or just starting out, it's never too late to stop—and it’s never too early to begin protecting your future.