You expose your lungs to more than 4,000 chemicals every time you smoke a cigarette or cigar. Many of these chemicals come from the tobacco smoke not the nicotine. According to the Better Health Channel website, the most damaging chemicals are tar, carbon monoxide, arsenic, lead, cadmium, radioactive compounds and--the one most detrimental to your lungs--hydrogen cyanide (see Reference 2).
Impaired Lung Cleaning
A thin layer of mucous, in which are found tiny, broom-like hairs called cilia, lines your breathing tubes and filter the air you breathe in. The mucous traps particles of dirt and pollution you breathe in, then the cilia pushes the dirt toward your lungs. Reflexively, you cough, spit up or swallow the dirt-filled mucous, and the dirt is forced out of your lungs (see Reference 3). Hydrogen cyanide from tobacco smoke impairs the cilia's ability to properly clean the lungs, and the chemicals from the tobacco smoke enter and settle inside your lungs. This increases your risk for lung cancer, chest infections, chronic infections and chronic obstructive pulmonary disease (COPD).
Mucous Buildup
According to the University of Pittsburgh Medical Center, smoking increases the cells that produce the protective mucous within your lungs. As a result, the amount of mucous increases and thickens, making you cough. If the cilia inside the lungs are unable to properly keep the mucous lining clean, the mucous becomes infected.
Irritation
Smoking causes irritation and inflammation of your airways and lungs. Air flow is reduced as the airways become narrow over time (see Reference 1). Just smoking one or two cigarettes can irritate the lungs and cause chronic coughing.
Premature Aging
It's natural for lung performance to decrease as you get older, however, smoking speeds up this process (see Reference 1).
Decrease in Oxygen
Within your lungs are air sacs called alveoli. When you inhale, the alveoli expand and absorb oxygen into the body. When you exhale, the alveoli deflate and expel carbon dioxide. Smoking damages the alveoli, impairing their ability to expand and take in oxygen and push out carbon dioxide. Breathing becomes difficult, and you tire easily. Your heart works harder to get oxygen to your body. Over time, this can result in heart disease and COPD (see Reference 3).
Lowered Immunity
Because smoking impairs the lungs' natural cleaning and repairing function, your immunity to infection is greatly diminished (see Reference 1). The chemicals in cigarette smoke can also change normal cells into cancerous ones.
