ConditionLungs & breathing
Smoking-Related Disorders
Smoking-related disorders are diseases caused or made worse by tobacco smoke, which contains thousands of chemicals including at least 70 known carcinogens. Smoking harms nearly every organ, causing lung and many other cancers, heart attack, stroke, COPD, peripheral artery disease, diabetes complications, erectile dysfunction and pregnancy complications. It remains the leading cause of preventable death in the US. Quitting at any age lowers risk, with benefits starting within days and growing for years.
Also called: Tobacco-related diseases, smoking-related illnesses, health effects of smoking
At a glance
- Scale
- Smoking causes about 1 in 5 deaths in the US, around 480,000 a year including secondhand smoke.
- Cancers
- Lung, mouth, throat, larynx, esophagus, stomach, pancreas, kidney, bladder, cervix, colon and acute myeloid leukemia.
- Heart and vessels
- Heart attack, stroke, peripheral artery disease, aortic aneurysm.
- Lungs
- COPD (emphysema and chronic bronchitis), worse asthma, more infections.
- Quitting
- Risk falls at any age. Medicines plus counseling roughly double or triple success.
When to get help
Call 911 or go to the ER
- Chest pain or pressure, sudden breathlessness, or stroke symptoms such as facial drooping, arm weakness or slurred speech: call 911 or your local emergency number
- Coughing up more than a few spoonfuls of blood
See a doctor within a day or two
- A cold, pale, painful leg or foot, or a non-healing wound on the foot
- Breathlessness that is getting worse over days
Book a routine appointment
- A cough lasting more than 3 weeks or a change in a smoker's cough
- Coughing blood even once, hoarseness lasting more than 3 weeks, or a mouth sore that will not heal
- Leg pain when walking that eases with rest
- Adults 50 to 80 who smoke or quit within 15 years with a 20 pack-year history: ask about lung cancer screening
- Men 65 to 75 who have ever smoked: ask about a one-time aortic aneurysm ultrasound
- Wanting help to quit smoking or vaping
How smoking causes disease
Tobacco smoke delivers:
- carcinogens that damage DNA, causing cancer
- carbon monoxide, which reduces the blood's oxygen-carrying capacity
- oxidizing chemicals that inflame and injure blood vessels and lungs
- nicotine, which is highly addictive and raises heart rate and blood pressure
These drive atherosclerosis, blood clotting, airway inflammation and lung tissue destruction.
Smoking-related diseases
Cancers
| Cancer | Smoking link |
|---|---|
| Lung cancer | Causes about 80% to 90% of lung cancer deaths |
| Mouth, throat and larynx | Risk multiplied with alcohol |
| Esophagus | Strongly linked |
| Bladder cancer | About half of cases |
| Kidney and pancreas | Increased risk |
| Stomach, liver, colon and rectum | Increased risk |
| Cervix | Increased risk with HPV |
| Acute myeloid leukemia | Increased risk |
Heart and blood vessel disease
- coronary artery disease and heart attack
- stroke
- peripheral artery disease, causing leg pain on walking and amputations
- abdominal aortic aneurysm
- Buerger's disease (inflamed, blocked small arteries in young smokers)
Lung disease
- COPD: emphysema and chronic bronchitis. Smoking causes most cases
- worsening asthma
- pneumonia, flu complications and tuberculosis
- some interstitial lung diseases
Other effects
- type 2 diabetes (30% to 40% higher risk) and worse complications
- erectile dysfunction
- reduced fertility, ectopic pregnancy, miscarriage, preterm birth, low birth weight, stillbirth and sudden infant death
- cataract and macular degeneration
- rheumatoid arthritis and Crohn's disease
- gum disease and tooth loss
- osteoporosis and hip fracture
- poor wound healing and more surgical complications
- premature skin aging
Secondhand smoke
Secondhand smoke causes lung cancer, heart disease and stroke in nonsmokers, and in children causes ear infections, asthma attacks, respiratory infections and sudden infant death syndrome. There is no safe level of exposure.
E-cigarettes and other products
E-cigarettes deliver nicotine with fewer toxicants than cigarettes, but are not harmless and are addictive. Cigars, pipes, hookah and smokeless tobacco also cause cancers and other diseases.
Benefits of quitting
| Time after quitting | Benefit |
|---|---|
| 20 minutes | Heart rate and blood pressure begin to fall |
| A few days | Carbon monoxide levels fall to normal |
| 1 to 12 months | Coughing and breathlessness decrease |
| 1 to 2 years | Heart attack risk drops sharply |
| 5 to 10 years | Mouth, throat and larynx cancer risk halved. Stroke risk falls |
| 10 years | Lung cancer risk about half that of a person who still smokes |
| 15 years | Coronary heart disease risk close to that of a nonsmoker |
Quitting before age 40 avoids most of the excess risk of death from smoking, and quitting at any age adds years of life.
How to quit
The USPSTF recommends that clinicians advise all adults who smoke to quit and offer counseling and medicines.
Medicines
- nicotine replacement therapy: patches combined with short-acting gum, lozenges, inhaler or spray work better than one form alone
- varenicline: the most effective single medicine
- bupropion
Support
- counseling from a doctor, pharmacist or quitline: in the US, call 1-800-QUIT-NOW
- text and app-based programs, such as Smokefree.gov
- setting a quit date, removing cigarettes, identifying triggers
Combining medicine and counseling gives the best chance of success. Many people need several attempts. Each attempt improves the odds.
Screening for people who smoke or used to
- lung cancer: yearly low-dose CT for adults 50 to 80 with a 20 pack-year history who smoke or quit within 15 years
- abdominal aortic aneurysm: one-time ultrasound for men 65 to 75 who ever smoked
- blood pressure, cholesterol and diabetes checks
Frequently asked questions
What diseases are caused by smoking?
Smoking causes lung and many other cancers, heart disease, stroke, COPD, peripheral artery disease, aortic aneurysm, type 2 diabetes, erectile dysfunction, pregnancy complications, cataracts, gum disease and osteoporosis, among others.
How soon after quitting smoking does health improve?
Benefits start within minutes to days as heart rate, blood pressure and carbon monoxide levels fall. Breathing improves within months, heart attack risk drops sharply within 1 to 2 years, and cancer risks keep falling for years.
Is it too late to quit smoking?
No. Quitting at any age reduces the risk of heart disease, stroke, lung disease and cancer and adds years of life. Even people who already have smoking-related disease benefit from quitting.
What is the most effective way to quit smoking?
Combining medicine with counseling works best. Varenicline or combination nicotine replacement (patch plus a short-acting form) are among the most effective medicines. Free quitline support is available at 1-800-QUIT-NOW in the US.
Is vaping safer than smoking?
E-cigarettes expose users to fewer toxic chemicals than cigarettes, but they are not risk-free, contain addictive nicotine, and their long-term effects are unknown. They are not recommended for nonsmokers or young people.
Sources
This guide was written from current patient and clinical guidance, including:
- US Surgeon General: The health consequences of smoking: 50 years of progress (2014); Smoking cessation (2020)
- CDC: Health effects of cigarette smoking; Benefits of quitting
- National Cancer Institute: Harms of cigarette smoking and health benefits of quitting
- World Health Organization: Tobacco fact sheet
- US Preventive Services Task Force: Tobacco smoking cessation in adults (2021)