Cigarette smoking is the greatest single cause of illness and premature death in the UK. Worldwide, tobacco kills 7 million people every year. Almost a million deaths are due to non-smokers being exposed to second-hand smoke.
This leaflet explains why smoking is so harmful. It also lists the benefits of stopping, and how to get help to stop.
January 2018 - Dr Hayley Willacy has read the recent UK research that shows the unexpected extent to which smoking even one cigarette a day is associated with major risks of heart disease or stroke - see Further reading below. The researchers say their findings have an important message for many smokers and health professionals who believe that smoking only a few cigarettes carries little or no harm. They argue that smokers should stop completely instead of cutting down to significantly reduce their risk of heart disease and stroke. They found that men who smoked just one cigarette per day had just under half of the extra risk of heart disease associated with smoking 20 cigarettes per day. They expected the risk to be much lower.
Smoking facts and figures
Up to half of all smokers die from smoking-related diseases. About 100,000 people in the UK die each year due to smoking. Smoking-related deaths are mainly due to cancers, chronic obstructive pulmonary disease (COPD), heart disease and stroke.
If you are a long-term smoker, on average, your life expectancy is about 10 years less than a non-smoker. Put another way, in the UK about 8 in 10 non-smokers live past the age of 70 but only about half of long-term smokers live past 70. The younger you are when you start smoking, the more likely you are to smoke for longer and to die early from smoking.
Many smoking-related deaths are not quick deaths. For example, if you develop COPD you can expect several years of illness and distressing symptoms before you die.
Smoking increases the risk of developing a number of other diseases (listed below). Many of these may not be fatal but they can cause years of illness and unpleasant symptoms.
The good news
- Stopping smoking can make a big difference to your health. It is never too late to stop smoking to greatly benefit your health. For example, if you stop smoking in middle age, before having cancer or some other serious disease, you avoid most of the increased risk of death due to smoking.
- Many people have given up smoking. In 1972 just under half of adults in the UK were smokers. By 1990 this had fallen to just under a third. At present, about a sixth of UK adults are smokers.
- Help is available if you want to stop smoking but are finding it difficult.
Cigarette smoke contains the following
Nicotine is is inhaled from the tobacco in cigarettes. It gets into the bloodstream and stimulates the brain. Nicotine is addictive.
If you are a regular smoker, when the blood level of nicotine falls, you usually develop withdrawal symptoms, such as:
- Difficulty concentrating.
- A craving for nicotine.
- Just feeling awful.
These symptoms are relieved by the next cigarette. This is the definition of nicotine addiction.
Most regular smokers are addicted to nicotine and smoke regularly to feel 'normal' and to prevent nicotine withdrawal symptoms.
Withdrawal symptoms begin within a few hours after having the last cigarette. If they are not relieved by the next cigarette, withdrawal symptoms become worse. If you do not smoke any more, the withdrawal symptoms peak after about 24 hours and then gradually ease over about 2-4 weeks.
About 2 in 3 smokers want to stop smoking but, without help, many fail to succeed. The main reason why so few smokers succeed, even though they want to stop smoking, is because nicotine addiction is strong and difficult to break. However, many more succeed with support and the use of nicotine replacement therapy (NRT), e-cigarettes or a smoking cessations medicine.
Read about how to stop smoking.
Tar which contains many chemicals
These deposit in the lungs and can get into the blood vessels and be carried to other parts of the body. Cigarette smoke contains over 4,000 chemicals, including over 50 known causes of cancer (carcinogens) and other poisons.
This chemical affects the oxygen-carrying capacity of the blood. In particular, in pregnant women who smoke, this causes a reduced amount of oxygen to get to the growing baby. This is thought to be the most important cause for the bad effects of smoking on the growing baby.
Which conditions are caused or made worse by smoking?
- Lung cancer. About 30,000 people in the UK die from lung cancer each year. More than 8 in 10 cases are directly related to smoking.
- COPD. About 25,000 people in the UK die each year from this serious lung disease. More than 8 in 10 of these deaths are directly linked to smoking. People who die of COPD are usually quite unwell for several years before they die.
- Heart disease. This is the biggest killer illness in the UK. About 120,000 people in the UK die each year from heart disease. About 1 in 6 of these is due to smoking.
- Stroke. You are up to six times more likely to have a stroke if you smoke and smoking doubles your risk of dying if you have a stroke.
- Other cancers - of the mouth, nose, throat, larynx, gullet (oesophagus), pancreas, bladder, neck of the womb (cervix), blood (leukaemia) and kidney are all more common in smokers.
- Circulation. The chemicals in tobacco can damage the lining of the blood vessels and affect the level of fats (lipids) in the bloodstream. This increases the risk of atheroma forming (sometimes called hardening of the arteries). Atheroma is the main cause of heart disease, strokes, poor circulation in the legs (peripheral arterial disease) and swollen arteries which can burst causing internal bleeding (aneurysms). All these atheroma-related diseases are more common in smokers.
- Buerger's disease causes inflammation of blood vessels, particularly in the hands and feet. It occurs mainly in smokers. It leads to narrowing and blockage of the blood vessels, causing pain. It may eventually lead to damage and death of the tissues in the hands and/or feet.
- Sexual problems. Men who smoke are more likely than non-smokers to have erection problems (impotence) or have difficulty in maintaining an erection in middle life. This is thought to be due to smoking-related damage of the blood vessels to the penis.
- Contraception. Women who smoke and are 35 or over cannot use contraceptives that contain oestrogen, because the risks of stroke are so much higher. Their choice of contraception is therefore reduced.
- Rheumatoid arthritis. Smoking is known to be a risk factor for developing rheumatoid arthritis. One research study estimated that smoking is responsible for about 1 in 5 cases of rheumatoid arthritis.
- Ageing. Smokers tend to develop more lines on their face at an earlier age than non-smokers. This often makes smokers look older than they really are.
- Fertility is reduced in smokers (both male and female).
- Menopause. On average, women who smoke have a menopause nearly two years earlier than non-smokers.
- Other conditions where smoking often causes worse symptoms. These include:
- Flu (influenza).
- Chest infections.
- Tuberculosis infection of the lungs.
- Long-term inflammation of the nose (chronic rhinitis).
- Eye damage due to diabetes (diabetic retinopathy).
- An overactive thyroid gland (hyperthyroidism).
- A disorder of the brain and spinal cord (multiple sclerosis).
- Inflammation of the optic nerve (optic neuritis).
- A condition causing inflammation of the gut (Crohn's disease).
- Smoking increases the risk of developing various other conditions. These include:
- Optic neuropathy - this is a condition affecting the nerve supplying the eye.
- A breakdown of the tissue at the back of the eye (macular degeneration).
- Pulmonary fibrosis.
- A skin condition called psoriasis.
- Gum disease.
- Tooth loss.
- 'Thinning' of the bones (osteoporosis).
- Raynaud's phenomenon - in this condition, fingers turn white or blue when exposed to cold.
Smoking in pregnancy
Smoking in pregnancy increases the risk of:
- Complications of pregnancy, including bleeding during pregnancy, detachment of the 'afterbirth' (placenta), premature birth, and ectopic pregnancy.
- Low birth weight. Babies born to women who smoke are on average 200 grams (8 oz) lighter than babies born to comparable non-smoking mothers. Premature and low-birth-weight babies are more prone to illness and infections.
- Congenital defects in the baby - such as cleft palate.
- Stillbirth or death within the first week of life - the risk is increased by about one third.
- Poorer growth, development and health of the child. On average, compared with children born to non-smokers, children born to smokers are smaller, have lower achievements in reading and maths and an increased risk of developing asthma.
How does smoking affect other people?
Children, non-smoking adults and unborn babies can all be affected by your smoke.
Children who live in a household with a smoker are more likely to have various health problems than children who don't. You don't even have to be smoking in the room or vehicle while a child is present, for them to be harmed by your smoke.
Learn more about smoking and others (passive smoking).
Other problems with smoking
- Your breath, clothes, hair, skin and home smell of stale tobacco. You do not notice the smell if you smoke; however, to non-smokers the smell is obvious and unpleasant.
- Your sense of taste and sense of smell are dulled. Enjoyment of food may be reduced.
- Smoking is expensive.
- Life insurance is more expensive.
- Finding a job may be more difficult as employers know that smokers are more likely than non-smokers to have sick leave. More than 34 million working days (1% of total) are lost each year because of smoking-related sick leave.
- Potential friendships and romances may be at risk.
What are the benefits of stopping smoking?
There are huge benefits to stopping smoking and they start as soon as you stop:
- Your life expectancy goes up.
- Your health improves, even if you are already have a smoking-related condition.
- You will start to look younger.
- You won't smell of stale tobacco.
- You will save money.
- You will have done something to make you feel proud.
Find out more about the benefits of stopping smoking.
How can I stop smoking?
The most important thing to do is to decide for yourself that this is something you want to do. The majority of smokers want to stop. Some do so easily but for others it's a real struggle, as smoking is very addictive. How addicted are you?
There are lots of different things out there available to help you to stop:
- Nicotine replacement therapy (NRT).
- Varenicline (Champix®).
- Bupropion (Zyban®).
- Support and advice is available from GPs, practice nurses or pharmacists - all you need to do is ask.
Read more about how to stop smoking.
Further reading and references
Hackshaw A, Morris JK, Boniface S, et al; Low cigarette consumption and risk of coronary heart disease and stroke: meta-analysis of 141 cohort studies in 55 study reports. BMJ. 2018 Jan 24360:j5855.
Smoking: harm reduction; NICE Public Health Guidance, June 2013
Smoking cessation; NICE CKS, October 2012 (UK access only)
Wu J, Sin DD; Improved patient outcome with smoking cessation: when is it too late? Int J Chron Obstruct Pulmon Dis. 20116:259-67. doi: 10.2147/COPD.S10771. Epub 2011 May 2.
Cahill K, Stevens S, Perera R, et al; Pharmacological interventions for smoking cessation: an overview and network meta-analysis. Cochrane Database Syst Rev. 2013 May 315:CD009329. doi: 10.1002/14651858.CD009329.pub2.
Cahill K, Lindson-Hawley N, Thomas KH, et al; Nicotine receptor partial agonists for smoking cessation. Cochrane Database Syst Rev. 2016 May 9(5):CD006103. doi: 10.1002/14651858.CD006103.pub7.
Anthenelli RM, Benowitz NL, West R, et al; Neuropsychiatric safety and efficacy of varenicline, bupropion, and nicotine patch in smokers with and without psychiatric disorders (EAGLES): a double-blind, randomised, placebo-controlled clinical trial. Lancet. 2016 Jun 18387(10037):2507-20. doi: 10.1016/S0140-6736(16)30272-0. Epub 2016 Apr 22.
Hartmann-Boyce J, McRobbie H, Bullen C, et al; Electronic cigarettes for smoking cessation. Cochrane Database Syst Rev. 2016 Sep 149:CD010216.
E-cigarettes: an evidence update; Public Health England, August 2015
Hughes JR, Stead LF, Hartmann-Boyce J, et al; Antidepressants for smoking cessation. Cochrane Database Syst Rev. 2014 Jan 81:CD000031. doi: 10.1002/14651858.CD000031.pub4.