Harms of Cigarette Smoking and Health Benefits of Quitting (Fact Sheet)

Does tobacco smoke contain harmful chemicals?

Yes. Tobacco smoke contains many chemicals that are harmful to both smokers and nonsmokers. Breathing even a little tobacco smoke can be harmful (1-4).

Of the more than 7,000 chemicals in tobacco smoke, at least 250 are known to be harmful, including hydrogencyanide, carbon monoxide, and ammonia (1, 2, 5).

Among the 250 known harmful chemicals in tobacco smoke, at least 69 can cause cancer. These cancer-causing chemicals include the following (1, 2, 5):

• Acetaldehyde
• Aromatic amines
• Arsenic
• Benzene
• Benzo[α]pyrene
• Beryllium (a toxic metal)
• 1,3–Butadiene (a hazardous gas)
• Cadmium (a toxic metal)
• Chromium (a metallic element)
• Cumene
• Ethylene oxide
• Formaldehyde
• Nickel (a metallic element)
• Polonium-210 (a radioactive chemical element)
• Polycyclic aromatic hydrocarbons (PAHs)
• Tobacco-specific nitrosamines
• Vinyl chloride

What are some of the health problems caused by cigarette smoking?

Smoking has been found to harm nearly every bodily organ and organ system in the body and diminishes a person’s overall health.    

Smoking is a leading cause of cancer and death from cancer. It causes cancers of the lung, esophagus, larynx, mouth, throat, kidney, bladder, liver, pancreas, stomach, cervix, colon, and rectum, as well as acute myeloid leukemia (1-3).

Smoking causes heart disease, stroke, aortic aneurysm (a balloon-like bulge in an artery in the chest), chronic obstructive pulmonary disease (COPD) (chronic bronchitis and emphysema), diabetes, osteoporosis,rheumatoid arthritis, age-related macular degeneration, and cataracts, and worsens asthma symptoms in adults. Smokers are at higher risk of developing pneumonia, tuberculosis, and other airway infections (1-3). In addition, smoking causes inflammation and impairs immune function (1).

Since the 1960s, a smoker’s risk of developing lung cancer or COPD has actually increased compared with nonsmokers, even though the number of cigarettes consumed per smoker has decreased (1). There have also been changes in the type of lung cancer smokers develop – a decline in squamous cell carcinomas but a dramatic increase in adenocarcinomas. Both of these effects may be due to changes in the formulation of cigarettes (1).

Smoking makes it harder for a woman to get pregnant. A pregnant smoker is at higher risk of miscarriage, having an ectopic pregnancy, having her baby born too early and with an abnormally low birth weight, and having her baby born with a cleft lip and/or cleft palate (1). A woman who smokes during or after pregnancy increases her infant’s risk of death from Sudden Infant Death Syndrome (SIDS) (2, 3). Men who smoke are at greater risk of erectile dysfunction (1, 6).

Cigarette smoking and exposure to tobacco smoke cause about 480,000 premature deaths each year in the United States (1). Of these premature deaths, about 36 percent are from cancer, 39 percent are from heart disease and stroke, and 24 percent are from lung disease (1). Smoking is the leading cause of premature, preventable death in this country.

Regardless of their age, smokers can substantially reduce their risk of disease, including cancer, by quitting.