CHAPTER 6

The Lungs Under Attack

How smoking damages the delicate tissues in your lungs and airways, causing a wide range of respiratory ills

PART 1 Irreparable Damage

Chronic Obstructive Pulmonary Disease (COPD) is most often a combination of two lung diseases that make breathing difficult. One is emphysema, in which the small tubes called bronchioles, leading to the alveoli, lose their elasticity and collapse. As a result, air is trapped in the alveoli and cannot be efficiently exhaled. The air sacs can overexpand and rupture. As alveolar damage builds up, victims have coughing and shortness of breath, and deliver too little oxygen to the blood. The other is chronic bronchitis, which is inflammation of the airways resulting in overproduction of mucus and frequent coughing. READ MORE

When you quit smoking, your lungs and airways definitely improve. You remove the toxic irritant that is responsible for destroying your lung tissue, and your body's natural defenses are better able to catch up to their repair work. However, COPD in long-time smokers results in some scarring of the lungs and destruction of the alveolar walls which never completely heal. The alveoli permanently lose some of their capacity to absorb oxygen and expel carbon dioxide because they have less surface area. And permanent damage to the lining of the airways affects their ability to expel invading objects and substances. The sooner a smoker quits, the less of this serious damage will accumulate. LESS

PART 2 How Your Defenses Go Down

Bronchial tubes are lined with hairlike cilia and mucus-producing goblet cells. Together, they form an important line of defense in your respiratory system. The mucus traps pollutants and germs, and the cilia wave the trapped invaders back toward the exit so they won't harm the more delicate tissues downstream. The system was not designed to manage the toxins in cigarette smoke, which cause inflammation in the airways. The result: cilia stop working, mucus is overproduced and the inflamed, damaged lining of your respiratory system cannot efficiently cast out harmful invaders. READ MORE

Cigarette smoke's most caustic ingredients are unstable bits of matter called free radicals. These atoms or molecules are missing electrons, and that's why they are unstable. They peel electrons away from surrounding matter to attain stability, which results in damage to whatever they touch-in this case, the lining of the lungs' airways. The body tries to repair the damage by sending in specialized white blood cells. Individuals have varying capabilities to mend the damage, which researchers believe is partly explained by individual genetic differences. The overall crisis caused by the free radicals bounding through the body, and the body's response, is referred to as oxidative stress. In the airways, it results in inflammation. In some smokers this causes progressive narrowing of the airways and further damage, which can lead to COPD. LESS

PART 3 Vulnerable to Attack

It Adds Up

120,000 Deaths...

Once a smoker has inflicted any amount of damage on his or her respiratory system, the likelihood of falling ill increases. An ailment triggered by an invading germ or contaminant-allergies, flu, the common cold, asthma-will have an easier time taking hold if the respiratory system's defenses are down. Then, once an infection or immune disorder begins, chances are it will last much longer than usual, because smokers lack key weapons to fight back. This could be why smokers miss an average of 6.16 work days with illness each year, compared to 3.86 days for nonsmokers. READ MORE

Say a coworker's big sneeze exposes you to a rhinovirus, the most common cold germs. A nonsmoker's body would jump into action. After sensing the invader, the goblet cells lining the airways would increase mucus production to surround the germs in sticky goo and slow their progress. Then, the hairlike cilia would increase their activity, waving the offending germs back toward the exit, away from the lungs. But smokers' cilia don't function properly. The result: The virus continues to replicate in the airways, but the system for getting rid of it malfunctions. The airways fill with both mucus and cold germs, and smokers have a tough time getting rid of them. LESS