Smoking damages almost every organ in your body. This includes your heart, lungs, and brain. It also affects your bones and raises your risk for certain cancers. These are all good reasons to quit.

Chemicals in tobacco damage the DNA of cells. DNA controls normal cell function. As a result, normal cell growth and development are changed. This can result in abnormal cells that cause cancer to grow. Smoking has been linked with many serious illnesses. It also increases signs of aging. A few of the health effects of smoking are listed below. Smoking can:

• Raise your risk for many types of cancer. These include cancer of the mouth, esophagus, lung, larynx, and windpipe (trachea). It can also increase the risk for stomach, pancreas, bladder, blood (leukemia), liver, kidney, and cervical cancer. Smokeless tobacco can cause cancers of the mouth, throat, esophagus, and pancreas.
• Harm your lungs and cause problems with breathing. This includes emphysema and chronic obstructive pulmonary disease (COPD).
• Raise blood pressure. This raises your risk for heart attack or stroke.
• Reduce blood flow. This can slow healing and cause wrinkles.
• Cause plaque to build up in your arteries (atherosclerosis). This can lead to heart attacks and strokes.
• Increase your risk for bone problems, such as bone thinning (osteoporosis). Smoking can also lead to poor bone healing. This can happen if you have a broken bone or bone surgery.
• Cause bleeding problems, miscarriage, stillbirth, or birth defects if you're pregnant.
• Cause problems with erections.

When you smoke, your breathing becomes shallow. Your lungs fill with smoke. Smoking cigarettes fills your body with chemicals. These include nicotine and tar. Here's how these things affect your body:

• Smoke. Cigarette smoke contains carbon monoxide. This gas takes the place of oxygen in your blood.
• Nicotine. This drug raises your blood pressure and heart rate. It reduces blood flow to your arms and legs. And it slows digestion.
• Tar. Tar is what's left after tobacco is smoked. This sticky brown material gums up your lungs. This causes less oxygen to get into your bloodstream.
• Other chemicals. Cigarette smoke contains more than 7,000 other chemicals. They include arsenic, lead, ammonia, butane, formaldehyde, and methanol. Many of these chemicals are known to cause cancer.

• CDC Quitline or 800-QUIT-NOW (800-784-8669)
• Smokefree.gov at www.smokefree.gov or 877-44U-QUIT (877-448-7848)
• American Lung Association at www.lung.org/quit-smoking or 800-LUNG-USA (800-586-4872)