Overall Effects

Smoking negatively affects every part of your body: 

Heart

• Smoking triples the risk of dying from heart disease among middle-aged men and women.
• Smoking is accountable for 81% of all chronic obstructive pulmonary disease (COPD) deaths.
• 21% of all coronary heart disease deaths are attributable to smoking (more than 170,000 deaths each year).

Lungs

• Is responsible for nearly 90% of lung cancer cases, (100,000 deaths each year).
• Can cause chronic coughing, increased phlegm, emphysema and bronchitis.

Cancers

• Deaths from lung cancer in women have exceeded breast cancer deaths.
• Smoking is a known cause of cancer of the larynx, oral cavity and esophagus.
• Smoking is a contributing cause of cancers of the bladder, pancreas, uterus, cervix, kidney and stomach.

Brain

• The risk of stroke is nearly doubled by smoking.
• Smoking is linked to a higher incidence of depression.

Bones and Skin

• Smoking is associated with the progression of atherosclerosis and hypertension.
• Smoking increases the risk and severity of rheumatoid arthritis.
• Smoking reduces the elasticity in the skin, which causes more prominent skin wrinkling.

Ears, Eyes, Nose, Throat and Mouth 

• Smoking is linked to hearing loss and vision problems, including cataracts.
• Smoking increases yellowing of the nails and teeth.
• Smoking is linked to gum disease and tooth loss.

Immune System

• Smoking creates more susceptibility to influenza, pneumonia, and colds.
• Smoking tends to lengthen the recovery time after surgery.

Reproduction

• Smoking may reduce fertility and lead to impotence among men. 

Source: A Report of the Surgeon General, Atlanta, GA 2006: The Health Consequences of Involuntary Exposure to Tobacco Smoke.