by Amy Scholten. MPH

Cigarette smoking is the number one cause of preventable death in the United States, killing 400,000 people a year. Smokers and people who live with smokers are at risk for a number of health conditions and diseases. A nonsmoker in a very smoky room for one hour inhales the same dangerous contaminants as he or she would by smoking 10 or more cigarettes. Smoking is even more dangerous for people who have heart disease, high blood pressure, diabetes, high cholesterol, or a family history of any of these diseases.

Diseases associated with smoking

Heart disease

Smoking is responsible for at least 20% of all deaths from heart disease in the United States. The more a person smokes, the higher his or her chances of developing coronary heart disease. Women who smoke have a 50% greater risk of having a heart attack than male smokers. Smoking plays a role in heart disease by:

• Lowering "good" (HDL) cholesterol
• Causing deterioration of the elasticity of the aorta
• Increasing the activity of the sympathetic nervous system, which regulates the heart and blood vessels
• Damaging the arteries

Cancer

Smoking is responsible for about 30% of all cancer deaths in the United States and plays a significant role in the changing cancer rates throughout the world. Smoking causes:

• 85% of all cases of lung cancer
• Between 60% and 93% of cancers of the throat, mouth, and esophagus

Smokers also have higher rates of:

• Leukemia
• Cancer of the kidney
• Stomach cancer
• Bladder cancer
• Pancreatic cancer
• Cervical cancer

Stroke
Smoking increases the risk of having a stroke, especially in individuals who smoke a pack or more of cigarettes a day, and in women who take oral contraceptives.

Dementia
A recent study suggests that smokers have 1.5 times the risk of developing Alzheimer's disease than those who don't smoke.

Lung disease
Smokers have much higher rates of pneumonia, flu, bronchitis and emphysema. Smoking also aggravates symptoms of asthma.

Pregnancy and birth problems

Smoking has been linked to:

• Infertility
• Ectopic pregnancy
• Miscarriage
• Low birth weight
• Premature delivery

Bone problems

• Women who smoke have a higher risk of developing osteoporosis.
• Smokers are more likely to develop injuries of the spine and degenerative disorders.
• Women who smoke may have a slightly increased risk of developing rheumatoid arthritis.

Peptic ulcers

Smoking increases acid secretion and decreases mucosal blood flow. The results of some studies have suggested that smoking delays the healing of peptic ulcers. Other studies suggest that smokers have more relapses once an peptic ulcer is healed.

Problems with male sexuality and reproduction

• Men who are heavy smokers are at increased risk for developing erectile dysfunction.
• Smoking can contribute to infertility by reducing sperm density and motility.

Skin, hair and teeth disorders

• Smokers tend to develop more wrinkles compared to nonsmokers.
• Smoking increases the risk for baldness and premature gray hair.
• Smokers are more apt to have tooth and gum problems.

Eye problems

• Smokers may have an increased risk of developing cataracts
• Smokers have an increased risk of macular degeneration.

Thyroid problems

• Cyanide in tobacco smoke may interfere with thyroid hormone.
• Female smokers with subclinical hypothyroidism have an increased risk of severe thyroid failure compared to nonsmoking women with the same condition.

Other problems
Some studies suggest that smokers are more likely to develop incontinence and hearing loss.

Problems in children (due to secondhand smoke)

Approximately 4 million children become ill from being exposed to secondhand smoke. Children exposed to secondhand smoke and smoking parents have an increased risk of:

• Sudden infant death syndrome (SIDS)
• Asthma, bronchitis, and pneumonia
• Childhood meningococcal disease
• Abnormal lung function
• Worsening of asthma
• An increase in lower respiratory infections
• Attention deficit disorder
• Conduct disorders
• Depression
• Substance abuse
• Decreased intellectual achievement
• Ear infections
• Eczema

The more cigarettes a person smokes each day, the greater the risk for disease. Cigar and pipe smoking are also dangerous and increase the risk of many diseases. Smokers can substantially reduce their risk of many of these diseases by quitting before there is irreverable damage.