Smoking Problems: Health Effects and How Quitting Helps

Everyday problems smokers notice

Many effects of smoking appear long before serious disease:

• Smoker's cough: a daily cough, worse in the morning, bringing up phlegm. Smoke paralyzes the tiny hairs (cilia) that clear mucus from the airways, so it collects overnight.
• Breathlessness and reduced fitness: carbon monoxide in smoke binds to red blood cells, reducing oxygen delivery.
• Frequent chest infections, colds and flu
• Bad breath, stained teeth and gum disease
• Reduced sense of taste and smell
• Wrinkled, dull skin and slower wound healing
• Erectile dysfunction from damaged blood vessels
• Reduced fertility in both men and women
• Worse asthma and more flare-ups

Serious diseases caused by smoking

Lung disease

• COPD: includes chronic bronchitis and emphysema. Smoking causes most cases. Symptoms are a daily cough, phlegm and gradually worsening breathlessness.
• Lung cancer: smoking causes about 80% to 90% of lung cancer deaths. Warning signs include a persistent or changed cough, coughing blood, chest pain, hoarseness and weight loss.

Heart and circulation

• Coronary artery disease and heart attacks: smoking damages the artery lining, raises blood pressure and makes blood more likely to clot.
• Stroke
• Peripheral artery disease: narrowed leg arteries causing leg pain on walking, and in severe cases ulcers and amputation.
• Abdominal aortic aneurysm: men aged 65 to 75 who have ever smoked are offered a one-time ultrasound screening in the US.

Other cancers

Smoking causes cancers of the mouth, throat, voice box, esophagus, stomach, pancreas, liver, kidney, bladder, cervix, colon and some leukemias.

Other conditions

• type 2 diabetes and its complications
• rheumatoid arthritis
• osteoporosis and hip fractures
• cataracts and age-related macular degeneration
• worse outcomes after surgery
• in pregnancy: miscarriage, stillbirth, low birth weight, premature birth and sudden infant death

Secondhand smoke and vaping

Secondhand smoke causes heart disease, lung cancer and stroke in nonsmokers, and asthma attacks, ear infections and sudden infant death in children. There is no safe level of exposure.

E-cigarettes (vapes) expose users to far fewer toxic chemicals than cigarettes, and some adults use them to quit smoking. They still contain addictive nicotine, are not safe for young people, pregnant women or nonsmokers, and their long-term effects are not fully known. Switching completely is better than continuing to smoke; using both offers little health benefit.

What happens when you quit smoking

Quitting at any age adds years of life. Quitting before 40 avoids most of the excess risk of death from smoking.

Normal side effects of quitting

Nicotine withdrawal causes cravings, irritability, anxiety, restlessness, poor concentration, increased appetite and sleep changes. These peak in the first week and fade over 2 to 4 weeks. A temporary increase in coughing is common as the lungs clear. Stop-smoking medicines ease withdrawal.

How to quit smoking

• Set a quit date within the next 2 weeks and tell people around you.
• Use medicine: varenicline or combination nicotine replacement therapy (a patch plus a fast-acting gum, lozenge, inhaler or spray) are the most effective options. Bupropion is another choice. See smoking and tobacco addiction for details on each.
• Get support: free quitlines (1-800-QUIT-NOW in the US), apps, text programs and counseling roughly double success when combined with medicine.
• Plan for triggers: coffee, alcohol, stress and other smokers. Change routines and remove cigarettes, lighters and ashtrays.
• Keep trying: most people need several attempts. Each attempt teaches you what to change next time.

Screening for smokers

The US Preventive Services Task Force recommends yearly low-dose CT lung cancer screening for adults aged 50 to 80 with at least a 20 pack-year smoking history who currently smoke or quit within the past 15 years. Ask your doctor whether you qualify.

Frequently asked questions

What are the most common health problems from smoking?

The most common are chronic cough, breathlessness and frequent chest infections. Smoking is the leading cause of COPD and lung cancer, and a major cause of heart attack, stroke, peripheral artery disease, many other cancers, gum disease, erectile dysfunction and pregnancy complications.

What symptoms should smokers not ignore?

See a doctor for a cough lasting more than 3 weeks or that has changed, coughing up blood, hoarseness, worsening breathlessness, chest pain, unexplained weight loss, leg pain when walking, or mouth sores that do not heal. Call 911 for chest pain or stroke symptoms.

How long after quitting smoking do lungs heal?

Cilia start to recover within weeks, and cough and breathlessness often improve within 1 to 9 months. Lung function decline slows to a normal rate. Damage from emphysema does not reverse, but stopping prevents further loss. Lung cancer risk keeps falling for years.

What is the most effective way to quit smoking?

Combining a stop-smoking medicine, such as varenicline or combination nicotine replacement, with behavioral support from a quitline, counselor or program gives the best results. This combination more than doubles quit rates compared with willpower alone.

Is smoking a few cigarettes a day harmful?

Yes. Smoking even 1 to 5 cigarettes a day raises the risk of heart disease and early death substantially. There is no safe level of smoking. Cutting down is a useful step toward quitting, but stopping completely gives the greatest benefit.