Tobacco is considered the greatest cause of preventable deaths in the United States and throughout the world. According to the American Heart Association and the National Health Interview Survey of 2008, 24.8 million men and 21.1 million women in the United States are smokers. Tobacco smoking causes many diseases affecting major organs of the body including heart, brain, and lungs.
Nicotine is the most active and important chemical component that causes dangerous effects on human body. It is a major risk factor for heart attacks; lung and mouth cancers and chronic obstructive pulmonary disease (COPD). Here, we will discuss some of the dangerous effects of smoking on human body.
It was revealed by the National Institutes of Health that a variety of cancers including cancers of oral cavity, esophagus, larynx, and lungs are caused by cigar smoking. It was observed that around 90% of the patients with oral cancer are smokers. Laryngeal cancer occurs about 20 to 30 times more in smokers than non-smokers. Smoking causes inflammation around the teeth which is termed as periodontitis. Adherent white plaques and patches occur on the membranes of oral cavity and is called as leukoplakia.
Effect on heart rate and blood pressure:
Increase in rate of heartbeat and a sharp rise in blood pressure are the immediate effects of smoking on heart and blood circulation. The heart rate increases by about 30 times during the first 10 minutes of smoking. Nicotine causes the blood vessels to get narrowed resulting in rise of blood pressure. The oxygen carrying capacity of the blood decreases as carbon monoxide increases heart rate. Long term effects of smoking include increase in levels of fibrinogen and cholesterol in blood increasing risk of heart attacks. Coronary heart disease (CHD), Peripheral vascular disease (PVD), aneurysm, artherosclerosis, and others are caused by the heart and circulation attacks.
Effect on lungs:
More than 80% lung cancer cases are caused by tobacco. Inability of cilia to remove the tar content of cigarette smoke leads to lung and laryngeal cancer. Chronic Obstructive Pulmonary Disease (COPD) is caused by smoking and is characterized by shortness of breath; persistent cough with sputum; and damage to lungs including emphysema and chronic bronchitis.
Effect on liver:
Numerous toxins are present in the cigarettes that lead to chronic inflammation and scarring of liver. This may increase the risk of diseases such as liver cancer, liver fibrosis, and Hepatitis B and C. Chemicals such as N-Nitrosodiethylamine, N-Nitrosopyrrolidine, and arsenic present in cigarettes are responsible for cause of liver tumors. The ability of liver to detoxify dangerous substances gets diminished by smoking.
Effect on brain dysfunction:
Nicotine reaches the brain within 10 seconds after inhalation. The carotid artery is the main artery that supplies blood to the brain. Fatty substances are built up in the carotid artery due to cigarette smoking. This decreases the supply of blood to the brain cells and results in stroke called as cerebral thrombosis. The risk of this stroke in smokers is about 1.5 times to that of non-smokers. Thickening and clotting of blood in brain may also be caused due to smoking.
Effect on digestive system:
Harmful effects of smoking can be seen on all parts of the digestive system. The decrease in strength of lower esophageal valve allows the acids of stomach to reflux into esophagus. This situation is termed as heartburn. The movement of bile salts from intestine to stomach is also promoted by smoking. Smoking increases the rate of formation of peptic ulcers.
Effect of skin and hair:
Collagen, a protein in skin, keeps the skin elastic. As nicotine affects collagen, elasticity of the skin is reduced. The tiny capillaries which nourish the skin are also constricted by nicotine, leading to formation of wrinkles. Healing process also gets affected by smoking and longer time is taken to heal a wound. The immune system is suppressed by the nicotine which leads to increase in susceptibility of viral infections of skin.
Premature thinning and graying of hair is seen in smokers. The chances of people becoming bald are twice in smokers than in non-smokers. Premature graying of hair is also 3 to 6 times common in smokers.
Effect on bone and muscle:
Smoking delays healing of fractures. Blood flow to all tissues is restricted by nicotine. Mostly it is restricted in newly forming tissues, which are involved in bone repair. The chemicals in tobacco are responsible for inhibition of development of new muscle and bone tissue cells. Smoking increases the risk of osteoporosis. Significantly lower bone densities are seen among women smokers and are more likely to suffer fractures. The risk of osteoporosis among women is 50% more in smokers than non-smokers.
Effect on respiratory system:
Entry of chemicals of tobacco into mouth and trachea causes irritation and chemical burns. It causes sore throat and pain. Cancer causing properties of certain chemicals may cause burns on trachea resulting in throat cancer. Many fatal diseases are caused by smoking including cancers of mouth, nasopharynx, larynx and lung. Increased risk of asthma, cough, bronchitis and pneumonia are seen in children who are exposed to passive smoking.
The feeling of euphoria and calmness are considered as the root cause for addiction to cigarettes. Nicotine triggers the release of dopamine in brain giving pleasure reaction. The psychological effects of smoking are dependent on the physical effect of nicotine on brain. When a person quits smoking, the psychological desire for cigarettes can last for many years, whereas the physical desire can be overcome within two weeks.
Smoking causes many dangerous effects on human body. The American Cancer Society estimated that 168,000 Americans died of cancer due to tobacco smoking in 2007. Yearly smoking causes 1 in 5 deaths in America. Hence, it is necessary to take serious steps for eradication of smoking habits. Many educational programs have to be conducted to make people aware of the harmful effects of smoking on human body.