One of the biggest problems of smoking is mortality. The problems that smoking causes are serious in many cases. The cigarettes affect everything from the internal functioning of organs to the efficiency of the body's immune system. There are approximately 4000 chemicals in cigarettes, hundreds of which are toxic like nicotine and Carbon monoxide and agents that produce cancer. All the toxic ingredients in cigarette smoke travel throughout the body causing damage in different ways. Nicotine reaches the brain within 10 seconds after smoke is inhaled. It has been also found in every part of the body and even in breast milk. Another ingredient smoke contains is carbon monoxide that binds to hemoglobin in red blood cells preventing affected cells from carrying a full load of oxygen. The agents that produce cancer in tobacco smoke damage important genes that control the growth of cells, causing them to grow abnormally or to reproduce too rapidly. Smoking affects the function of the immune system and may increase the risk for respiratory and other infections by changing biologic chemicals that you have in your body. So it is very important to know what problems the cigarette brings to the body. Cigarettes reduce your life and kill you slowly over time, given you more lung problems like difficulty to breath and it will also make you easy target for common diseases.