Tobacco Smoking and Gene Mutation
Even though most smokers do not want to admit that cigarette smoking is the primary risk for lung cancer, statistics show that smoking can actually cause cell's gene mutations which lead to cancer occurrence. Gene mutations actually make the cells unable to correct the damages inside the lungs that are made by the carcinogenic substances inhaled while smoking. In order to better understand this thing, you should know that the carcinogens belong to a class of substances that are responsible for damaging the DNA, thing that develops cancer. The most important substances that damage the DNA inside lungs are tobacco, arsenic, asbestos, car exhaust fumes and radiations, such as x-rays.

The Most Dangerous Factor for Lung Cancer
From all the above-mentioned factors, tobacco smoking is the most dangerous one as it exposes our bodies to a wide range of carcinogens. When our lungs are exposed to carcinogens, the free radicals formed try to get electrons from other molecules. This way, they actually damage a series of new cells which cannot divide and function normally anymore. So, when a person lights up a cigarette, he or she actually starts this process again, destroying every time even more cells. Of course, the exposure to the second-hand smoke has the same effect on lungs, so that it definitely highlights a high risk for lung cancer.  

Lung Cancer Predisposition
Today, the statistics show that about 87 percent of lung cancer cases are related to inhaling the carcinogens of tobacco smoke. Even more, many people have a predisposition to developing lung cancer that is inherited from other family members. Of course, these persons should never start smoking, as the occurrence of lung cancer is almost a certainty. When it comes to lung cancer, the symptoms are quite varied and usually they depend on the spot the cancer is located. In addition, the symptoms also depend on the type of cancer, how big the tumor is and where it has spread.  

Lung Cancer Symptoms
A very discouraging aspect of lung cancer is that fact that it might take a few years until the sufferer has the first symptoms. In general, the first symptoms appear when cancer is already in an advanced stage. In addition, the symptoms of lung cancer also affect chest and air passages. Some of the symptoms of lung cancer are persistent coughing, pains in the back or chest from coughing, difficulty in breathing and even swallowing, changes of sputum's color, voice hoarseness, chronic pneumonia and bronchitis, wheezing, and coughing up blood.

Lung Cancer Complications Due to Smoking 
If the person keeps smoking, some additional symptoms might appear especially because of the spreading of cancer. This way, the lymph nodes swell and in some cases, the cancer spreads to the brain, thing that causes a series of symptoms such as seizures, headaches and vertigo. As well, the liver might react and become larger while bones describe a painful condition, showing a brittle structure that is prone to fractures. As you are able to see, cigarette smoking destroys people's lives. For this reason, you should definitely stop smoking right away so that you might get the chance to prevent lung cancer occurrence and live a life without pains and regrets.