Harm to human body by smoking – danger of smoking
When cigarette smoke is inhaled, thousands of chemicals get into your bloodstream and travel throughout your body. These chemicals cause damages to different parts of the body.
Eyes: Chemicals in tobacco cause damage to the macula (the most sensitive part of the retina, the back of the eye).
Tiny blood vessels can burst through the macula, leading to irreversible damage. According to the recent research, there is a strong association between smoking and a number of common eye diseases, including Graves' ophthalmopathy, age- related macular degeneration, glaucoma and cataract. Smoking causes morphological and functional changes to the lens and retina due to its atherosclerotic and thrombotic effects on the ocular capillaries. Also, it enhances the generation of free radicals and decreases the levels of antioxidants in the blood circulation, aqueous homour and ocular tissue. Eventually, continuous smoking may perpetuate further damage and lead to permanent blindness.
Mouth, throat and oesophagus: Smoking is a risk factor for all cancers associated with the larynx, oral cavity and oesophagus. Over 90% of the patients with oral cancer (includes cancers of the lip, tongue, mouth and throat) are smoker, and the risk for these cancers increases with the number of cigarettes smoked. Heavy smokers have laryngeal cancer mortality risks 20 to 30 times greater than non-smokers. The combined effect of tobacco and alcoholic drink imposes a much higher risk of oral and pharyngeal cancers by 35-fold.
Heart and circulation: Two immediate effects of smoking on heart and circulation are (1) an increase in your heartbeat rate, (2) a sharp rise in blood pressure. These responses are caused by nicotine which acts on the nervous system, causing the heart rate to rise and blood vessels to constrict. This narrowing of the blood vessels causes the blood pressure rise and strain is put on the heart. The carbon monoxide in cigarettes depletes the oxygen carrying capacity of a smoker's blood. This means that the heart has to pump harder to get enough oxygen to the rest of the body.
Smoking can also affect the blood in the long term: increase in the blood cholesterol and fibrinogen levels. Both these factors mean blood will clot more easily and this will increase the risk of having a heart attack, caused by a blood clot forming in the heart. The heart and circulation attacks caused by smoking include : Coronary heart disease (CHD), Aneurysm, Peripheral vascular disease (PVD), stroke etc.
Lungs: The tar content of cigarette smoke damages the cells in the airways of the lung, making the cilia unable to sweep away the harmful substances. Eventually this damage can produce cells that grow in an uncontrolled way leading to cancer of the lung or larynx. Moreover, harmful substances from the smoke are detected by the protective cells of the body and these cells move to the lung and try to defend it, but are destroyed by the cigarette smoke. The dead cells release substances that damage the structure of the lung, which leads to chronic bronchitis and emphysema. Tobacco accounts for more than 80% of the lung cancer cases. The observed relationship between tobacco smoking and the incidence of lung cancers appears to depend on factors such as: i) the daily dose of tobacco; ii) the duration of regular smoking and iii) the form in which tobacco is smoked (cigarettes, cigars, pipes).
Brain: Cigarette smoking has been linked to the buildup of fatty substances in the carotid artery, the main neck artery supplying blood to the brain. Blockage of this artery may cut off the blood supply to the brain cells, which results in stroke (cerebral thrombosis). Also, nicotine raises blood pressure; carbon monoxide reduces the amount of oxygen your blood can carry to the brain; and cigarette smoke makes the blood thicker and more likely to clot. Smokers are more likely to develop stroke than non-smokers, with the overall relative risk of stroke in smokers being about 1.5times that of non-smokers.
Digestive system: Smoking has been shown to have harmful effects on all parts of the digestive system, contributing to such common disorders as heartburn and peptic ulcers. It also increases the risk of Crohn's disease and possibly gallstones.
Risk of stomach cancer caused by smoking increases with duration of smoking and the number of cigarettes smoked.
Liver and pancreas: Nearly 50% of the bladder and kidney cancer in men are caused by smoking, with lower contribution for women. Cigarette smoke can interact with chemical (especially aromatic amines) in the work place to produce bladder and kidney cancer. Also, approximately 30% of all deaths from pancreatic cancer are attributable to cigarette smoking.
Skin and hair: Just 10 minutes of cigarette smoking decreases the body's and skin's oxygen supply for almost an hour. Smoking robs the skin of collagen which keeps the skin elastic. Smokers get more and deeper wrinkles all over their faces because nicotine constricts the tiny capillaries that nourish the skin. Smokers in their 40s often have as many facial wrinkles as non-smokers in their 60s. Smoking interferes with the healing process, it takes longer to heal and there is more scarring. Smokers are also prone to premature thinning and graying of the hair. Men who smoke are twice as likely to become bald as are men who do not smoke, and premature graying is 3 to 6 times more common in smokers.
Bone and muscle: Smoking delays the healing of fractures, and in some smokers bone healing is indefinitely delayed. Nicotine restricts blood flow to all tissue, especially in the newly forming tissues that are involved in the bone repair. Moreover, tobacco smoke chemicals are poisons that also inhibit the development of new tissue cells. The tissue of smokers does not get an adequate blood supply to promote healing, thus smokers are at a much higher risk of developing osteoporosis. Male smokers are also affected because smoking negatively affects the production of bone cells. Women with a smoking history have significantly lower bone density and are much more likely to suffer fractures. Furthermore, their earlier menopause add to the risk of osteoporosis. Studies show that women who use tobacco have a 50% higher risk of osteoporosis than nonsmokers. Smokers also have poorer muscle strength, agility and balance.