The effects of smoking in the human body

Hazardous Effects of Smoking on the Human Health

Since modern people live and eat satisfactorily, they began to concern themselves more about their health. These days we frequently can see many male adults who are smoking. Moreover, the smoking rate of teenagers and women has lately been getting higher; thus, the problem becomes very serious. Although people know that smoking is bad and harmful, they seem difficult to quit smoking. People might not fully know negative effects of smoking. They must attempt to learn how horribly undermine their health while they are smoking. Once they understand the serious relation between smoking and its effects, then they would be more determined and easier to quit smoking with obtained knowledge for preventing smoking. Then what does smoking actually cause on human health, and how seriously appalling are its effects?

Smoking causes various diseases such as chronic bronchitis and various kinds of cancer: lung cancer, larynx cancer, cancer of the esophagus, etc. Tobacco, which people smoke, is a toxic substance, and a main ingredient that causes the toxic is nicotine. This nicotine has a medical action which is similar to toxic substance such as a narcotic. When it is the first time to smoke or when a smoker smokes a lot, it gives various symptoms such as vomiting, giddiness, headaches, etc. by nicotine. Nicotine is very poisonous; therefore, if a human’s body absorbs too much nicotine in their blood at once, most of the people die. The most important medical action of nicotine is a mental effect. Nicotine makes smokers feel a sense of mental stability and gives a sedative effect that helps to relieve the tension. Most of all, these medical actions of nicotine cause a habit which makes people smoke continually.

The smoke of tobacco includes carbon monoxide; therefore, smokers could be in hypoxia, because the use rate of oxygen by smokers is much lower than the use rate of oxygen by nonsmokers. Smoking makes smokers feel headache, dizziness, and fatigue, makes eyes get flickering, gives a sense of vomiting, makes the heart beat faster, gives an oppressive feeling of the breast, and makes a smoker have difficulty in breathing, and even a state of stupor follows. If these states get worse, it gives a state of unconsciousness and finally makes people die. Smoking does not only give people these states, but it also causes various diseases: coronary heart disease, lung cancer, esophageal carcinoma, oral cancer, laryngeal cancer, kidney cancer, cervical cancer, pancreatic cancer, bladder cancer, et cetera.

There is also the addiction of nicotine in tobacco. According to the Department of Health and Human Services in the United States, “Cigarettes and other forms of tobacco are addicting. Nicotine is the drug in tobacco that causes addiction. The pharmacologic and behavioral processes that determine tobacco addiction are similar to those that determine addiction to drugs such as heroin and cocaine.” It is obviously true that many smokers are having trouble quitting smoking even though many campaigns for smokers’ health are still going on. Only the reason why a lot of smokers keep smoking with the determination for quitting smoking is because nicotine gets their bodies addicted to smoking. As long as smokers are exposed to the addiction of nicotine, they would need more cigarettes to suffice for their impulse to smoking.

However, people discovered that many of these toxic substances could be useful for medicinal purposes and also gave pleasure when consumed. The modern neuro-physiology has proven that nicotine is more effective when inhaled into the lungs. The smoke is mild enough to be inhaled deeply into the alveoli of the lungs from where it is rapidly absorbed. In addition, it takes about seven seconds for nicotine to be absorbed through the lungs to reach the brain. On the other hand, it takes 14 seconds for nicotine to travel from the arm to brain after an intravenous injection. Nicotine could unlock and combine with receptors throughout the body, thus it could activate other neurotransmitters, namely serotonine and dopamine. The small doses of nicotine could result to a sense of well-being while large doses may cause depression and overdoses may kill. Nicotine is highly addictive, as explained by West and Grunberg (as cited in Goodman, 1993), tobacco smoking could get regular and compulsive and the withdrawal syndrome usually accompanies tobacco abstinence. During the 1990s, the US Surgeon General reported that “smoking represents the most extensively documented cause of disease ever investigated in the history of biomedical research” (as cited in Goodman, 1993, p. 242). Passive smokers or second hand smokers are also affected since they also inhale the smoke.

There are several studies linking human genes to nicotine addiction like the the Swedish and Finnish twin registries (Kaprio, Koskenvuo, & Sarna, 1981) that support the conclusion of a significant contribution of genetic effects to smoking. Genes are the basic biological units of heredity and the segments of deoxyribonucleic acid (DNA) needed to contribute to a function. To make new proteins, the living cell uses the genetic code of the macromolecule DNA, which stores all the information about the sequence of amino acids in the cell’s proteins. The identity and position of each amino acid in the protein chain is coded by nucleotides on the DNA, called codons.

Among the numerous neurochemical effects of nicotine is its initial action on the nicotinic cholinergic receptors. Nicotine produces an increase in the rate of release and turnover of acetylcholine and catecholamines. It has been hypothesized that nicotine enhances the experience of pleasure through its effects on the dopaminergic system, while its ability to reduce anxiety and tension is mediated through stimulation of ACTH and cortisol; nicotine’s ability to enhance task performance may be due principally to its action on the cholinergic and noradrenergic pathways (Pomerleau & Pomerleau, 1984). This only shows that it is possible that gene variants play a role in receptor functioning in one or more of the systems on which nicotine exerts an effect. In a research conducted by Tapper, et al. (as cited in Secko,2005), they discovered that a “mutation in the α4 nAChR subunit lowers the threshold of nicotine dependence in mice” (p. 175). The same article implicates that α4 and β2 nAChR subunits could affect nicotine dependence.

One of the disadvantages of the relationship of gene variance and nicotine addiction is the heterogeneity of human beings. Thus, genetic make-up of every human is different from each other. Also, the genetic influences on different stages of smoking may also not be identical. Thus, researchers have to study well-defined subgroups of smokers with clearly characterized phenotypes to avoid problems of population stratification. The advantages of the new findings regarding the relationship of gene variance and nicotine addiction is that as more genetic variations are discovered that are associated with the addiction, the medical field would be able to better understand how to prevent and treat human addictive disorders. The insights on genetic variance could contribute to more effective strategies to reduce smoking. Moreover, since there is no single medication that is likely to be safe and efficacious for a majority of persons with nicotine dependence, it will be useful to develop genetics-based methods and other tools to predict therapeutic response in subgroups of nicotine-dependent persons.

Female smokers do harm to embryonic health, and smokers cause nonsmokers to inhale indirect smoking, which causes damage similar to smoking, by breathing in the smoke made by smokers. In addition, teenage smoking is very bad, because smoking is more harmful for teenagers, and starting smoking at teenage makes it easier to fall deeper into toxic symptoms of nicotine. Teenage smoking is connected to juvenile delinquency and also is causing serious effects to emotional and social problems. The problem of smoking is this serious; however, as the time goes, the population increases, and as the population increases, the smoking quantity increases. In order to solve this problem, there is one method always suggested: people must stop smoking for themselves and others. Smokers have to know the reason why they smoke, so they could take on other habits or other work instead of smoking.


  • Goodman, J. (1993). Tobacco in History: The Cultures of Dependence. London and New York: Routledge.
  • Kaprio J, Koskenvuo M, Sarna S. (1981). Cigarette smoking, use of alcohol, and leisure time physical activity among same-sexed adult male twins. In L. Gedda, P. Parise, & W. E. Nance (Eds.), Twin Research 3: Part C, Epidemiological and Clinical Studies (pp. 37-46). New York: Liss.
  • McGee, H. (1986) On Food and Cooking. The Science and Lore of the Kitchen. London: HarperCollins.
  • Pomerleau, O. F. & Pomerleau C. S. (1984). Neuroregulators and the reinforcement of smoking: towards a biobehavioral explanation. Neuroscience and Biobehavioral Reviews, 8, 503-513.
  • Secko, D. (2005). Craving nicotine: It’s in the genes. Canadian Medical Association Journal, 172 (2), 175-176.