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Smoking & tobacco

Facts about smoking

How smoking hurts your health

Smoking seriously hurts your lungs:

1. Smoking damages your lungs' natural cleaning and repair system and traps cancer-causing chemicals in your lungs.

Smoking destroys the tiny hairs (cilia), which line the upper airways and protect against infection. Normally, there is a thin layer of mucous and thousands of these cilia lining the insides of your breathing tubes. The mucous traps the little bits of dirt and pollution you breathe in, and the cilia move together like a wave to push the dirt-filled mucous out of your lungs. Then you cough, swallow, or spit up the mucous, and the dirt is out of your lungs.

When your lungs' natural cleaning and repair system is damaged, germs, dirt and chemicals from cigarette smoke stay inside your lungs. This puts you at risk for chronic cough, chest infections, lung cancer and COPD. Learn more about what's in cigarettes.

2. Smoking permanently damages the alveoli (air sacs) in the lungs, making it hard to breathe.

The alveoli, little air sacs at the tips of your lungs, are built like tiny, stretchy balloons. As you breathe in, your alveoli help you absorb oxygen into your body, and as you breathe out, alveoli help get rid of the waste gas carbon dioxide. (Carbon dioxide is a harmful gas that's also found in car exhaust fumes.) Smoke damages you lungs so much that your alveoli become less stretchy. This means it's harder for your lungs to take in the oxygen you need and harder to get rid of carbon dioxide. When the alveoli are damaged like this, you can feel short of breath and tired. Your heart has to pump much harder to give your body the oxygen it needs. Over time, this damage can lead to COPD and heart disease.

Signs of lung damage from smoking

It's common for smokers to ignore or downplay the symptoms of lung damage:

  • feeling out of breath when walking up a short flight of stairs
  • coughing
  • spitting up mucous
  • repeat chest infections

These are not signs of aging or simply being out of shape. These are real signs of the damage that smoking is doing to your lungs. If you have these signs of smoking damage to your lungs, see you doctor. Unless you do something now, these symptoms will keep getting worse.

How smoking hurts the rest of your body

Smoking doesn't just damage your lungs. It puts you at high risk for dozens of other serious disease, including cancer. Read more about the health effects of smoking.

I've been smoking all my life - why should I stop now?

It's never too late to quit. By stopping now, you can reduce your risk of cancer, lung and heart disease. You can also stop your lungs from getting even more damaged. Within one year of quitting smoking your risk of dying of a heart attack drops by half. Quitting is worth it. You're worth it. Read more about the benefits of quitting.