How does smoking cause cancer?

According to Cancer Research UK, smoking is the leading preventable cause of cancer not just in the UK, but worldwide. Although cigarette smoking is the biggest risk factor for lung cancer, it can affect the entire body. In fact, it’s known to cause at least 15 different types of cancers.

There’s no way to smoke safely – and even those who don’t smoke can suffer the effects through second hand smoking – and stopping smoking is the best way to prevent the risk of developing smoking-related cancers. Quitting is perfectly possible, and with the help of ‘stop smoking’ services, receiving treatment can be made easier, although it’s often not needed. From identifying the main types of cancer that smoking can cause, to offering advice on how to quit smoking, read on to learn more.

Chronic inflammation and DNA damage

Over 5000 chemicals are released when smoking a cigarette, and at least 70 of these are known to cause cancer. Once inhaled, these chemicals spread to the lungs and then work their way around the entire body, causing extensive damage to DNA. Inflammation is a helpful process within the body, but if it prolongs and becomes chronic, it can be seriously damaging. Long-term inflammation may, in some circumstances, aggravate cells whose DNA is already damaged.

Which cancers are associated with smoking?

There is a clear link between smoking and certain cancers, with two of the most common smoking-related cancers being lung and bowel cancer.

Smoking can cause cancer almost anywhere in the body. The following can also be affected:

What other conditions are linked with smoking?

Smoking doesn’t just cause cancer – it’s linked to many other health conditions, as it can damage almost every organ in the body.

The following conditions are also linked with smoking:

● Cardiovascular disease (CVD) – including coronary heart disease, hypertension (high blood pressure), heart attack, stroke, aneurysms (bulge or weakness in the artery), and peripheral artery disease – where narrowed arteries reduce blood flow to the arms or legs.
● Chronic obstructive pulmonary disease (COPD) – which includes emphysema and chronic bronchitis
● Tuberculosis – the risk of contracting the infection is increased by smoking
● Eye disease – including age-related macular degeneration, cataracts, glaucoma and diabetic retinopathy, and dry eye syndrome
● Rheumatoid arthritis

When should you see your GP?

If you smoke, you may develop a long-term smoker’s cough. The chemicals inhaled from smoking cause inflammation, as well as changes to your airways. Small hairs (cilia) line your airways, and help to keep them clear, but smoking damages them. As your airways will produce more mucus than normal if you smoke, coughing is the body’s natural way to compensate for these changes.

A regular cough should usually clear up on its own within three to four weeks, but you should contact your GP if your cough lasts longer than three weeks, as this could indicate an underlying health condition, including lung cancer. Most GPs would offer a chest x-ray if you’ve been coughing for 4 weeks or more.

If the following also applies to you, it’s important that you book an appointment with your GP:

• You can’t stop coughing, or your cough is getting worse quickly
• You feel very unwell
• You’re experiencing chest pain
• You’re losing weight without trying
• The side of your neck feels painful and swollen
• You’re more short of breath than usual
• You have a weakened immune system – for example, because of chemotherapy or diabetes

If you start coughing up blood, you must see your GP urgently.

How to stop smoking

Ultimately, the best way to decrease your risk of developing smoking-related conditions, and improve your overall health, is to stop smoking. This can seem daunting, but you can achieve anything you set your mind to, and there are resources available to help you quit if you need them.

The NHS offers local, free ‘stop smoking’ services, where you’ll be greeted by friendly, professional advisers who can offer helpful information and advice on how best to quit. Usually, you’ll be scheduled for a one-on-one appointment with an adviser, but some locations may offer group sessions and drop-in services, too.

If you want to contact a ‘stop smoking’ adviser, you can get a referral from your GP or pharmacist, or you can ring up yourself directly to schedule an appointment:

• England:

• ‘Stop smoking’ services in England
• Contact 0300 123 1044 for the free Smokefree National Helpline

• Scotland:

• ‘Stop smoking’ services in Scotland
• Contact 0800 84 84 84 for the free Quit Your Way Scotland helpline

• Wales:

• ‘Stop smoking’ services in Wales
• Contact 0800 085 2219 for the free Help Me Quit helpline

• Northern Ireland:

• ‘Stop smoking’ services in Northern Ireland

Take more control of your health and wellbeing, with the Evergreen Life app. Our handy health and fitness section can be used to record all sorts of health information. Give it a try!

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