Why is smoking so harmful to my health?

For most smokers, the tobacco smoke is more dangerous to their health than the nicotine. Long-term inhalation of tobacco smoke exposes every cell of your body to powerful chemicals that can cause cancer and cell mutations, and that ultimately cause tobacco-related illnesses. Tobacco smoke from cigarettes, cigars, and pipes contains over 4,000 chemical compounds and breathable, suspended particles. Some of the chemicals present in tobacco smoke have been proven to cause cancer and increase the risk of birth defects. These include ammonia, arsenic, benzene, cadmium, carbon monoxide, formaldehyde, lead, mercury, naphthalene, urethane, and a variety of nitrosamines (potent human carcinogens). Formaldehyde, ammonia, urethane, and naphthalene are contained in household products with labels telling you to avoid inhaling them. There are also radioactive chemicals in tobacco smoke, like polonium-210. So far, over 40 chemicals have been found in tobacco smoke that are known human carcinogens. This means that these chemicals have been proven to cause cancer not only in laboratory animals, but also in people. These chemicals make smoking such high risk to the health of any smoker.

The carbon monoxide found in tobacco smoke is the same gas that you find in your car's exhaust system and a faulty gas heater in your home. It is a colorless and odorless gas that interferes with your body's ability to use the oxygen that you inhale to fuel your cells. Normally, oxygen binds to your red blood cells by attaching to a molecule called hemoglobin. When you smoke, carbon monoxide attaches to your hemoglobin instead of oxygen, and deactivates these red blood cells from fueling your body. Eventually, the carbon monoxide falls off the hemoglobin, but it can be replaced if you are still smoking a tobacco product. Up to ten percent of your body's hemoglobin can be deactivated when you smoke. This is how smoking can affect your stamina and athletic ability. Increased levels of carbon monoxide in your blood also means less oxygen to your brain. Fortunately, the body is able to eliminate most of the carbon monoxide quickly, and within a few days of quitting smoking, most people feel more energetic and less shortness of breath.

Tar is a dark substance that delivers nicotine to the lungs, and it also contains the other chemicals discussed above. When tobacco smoke is inhaled, most of the tar is retained for a while in the mucous lining of the lungs and then mostly distributed throughout the body. After years of smoking, tar can collect in the lung and cause tobacco-related illnesses. If you drink alcohol and smoke, more of the carcinogens in the smoke are dissolved into the bloodstream because alcohol is a very effective solvent.

The tobacco companies know that many smokers are concerned about the health effects of smoking, and they produced "low tar/low nicotine" cigarettes to appeal to health-concerned smokers. Many smokers believe that these cigarettes are a "safe" alternative to quitting smoking. However, the truth is that there is no "safe" cigarette. There are no current regulations for the use of the word "light" in a cigarette's name, and "light" could mean that the cigarette weighs less than the regular brand, or that the nicotine content is only slightly less than the average one milligram nicotine level of the average regular cigarette. Also, many smokers tend to compensate for lower levels of tar and nicotine by smoking more cigarettes per day, or by inhaling more deeply and intensely than with regular cigarettes. Unless you smoke "ultra low tar/nicotine" cigarettes (cigarettes with less than 0.1 milligram), you cannot reduce your exposure to the risks of cigarette smoking by changing brands.