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Cigarettes: No. 1 enemy of lungs

For every cell in the human body, oxygen is an absolute necessity. The vital task of collecting oxygen from the air and bringing it into the body falls to two spongy, pink organs encased in the rib cage—the lungs. And these essential organs come under attack every day.

With each breath, the lungs are exposed to every impurity in the air around us, including car exhaust, chimney smoke, dust, pollen, bacteria and viruses. But all of these offenders together can't compete with cigarettes, the uncontested worst enemy of healthy lungs.

Every structure and function of the lungs is impaired by cigarette smoke, according to the National Institutes of Health and the U.S. Department of Health and Human Services. When cigarette smoke meets lung tissue, the effects include:

  • Damaged cilia. Delicate, hairlike cilia line the airways in the lungs. They sweep mucus, dirt and other debris out of the airways. Smoking damages the cilia, letting mucus, poisons and other particles build up inside the lungs.
  • Altered cells. Smoking damages the DNA in lung cells, causing abnormal cell growth that can eventually lead to lung cancer. Smoking also causes cellular changes that interfere with the natural ability of the lungs to destroy bacteria and viruses, leaving the body more vulnerable to infection.
  • Swollen lung tissue. Cigarette smoke irritates and damages tissues in the lungs. This can lead to scarring and chronic cough. 
  • Excess mucus. Cigarette smoke irritates the airways. In response, the airways secrete extra mucus, leaving less room for air to travel to or from the lungs.
  • Destroyed air sacs. The alveoli are one of the most important structures in the lungs. These tiny balloonlike air sacs have delicate walls that allow oxygen to pass into the blood and carbon dioxide to pass out of the blood. Repeated exposure to cigarette smoke breaks down these walls. Over time this damage can lead to emphysema, a lung disease that progressively reduces the amount of oxygen the lungs can absorb, makes breathing increasingly difficult and slowly reduces the body's oxygen supply.
To protect your cells, your life and your breath, keep your lungs healthy. The best way to do this is by never smoking cigarettes. Next best? If you smoke, stop.

reviewed 6/7/2019

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