With a staggering 1.1 billion people worldwide smoking cigarettes, it’s no surprise that nicotine addiction has become one of the most studied addictions in modern science. Both a physical dependence and psychological habit, smoking tobacco is the leading cause of preventable, premature deaths and illnesses in the world.
Scientific Evidence Suggesting a Genetic Link
A widespread addiction with high mortality rates poses the question: Is genetic predisposition at play? A study published by the National Library of Medicine found that genetic factors play a role in developing smoking habits and addiction. These findings revealed that heritability estimates for smoking initiation range from 0.32 to 0.78, indicating a moderately heritable trait.
Similarly, researchers from the U.S., U.K., and New Zealand conducted a long-term study based on a previously developed genetic profile that leads to heavy smoking habits. The study monitored 1,000 individuals from birth to age 38 to determine if a genetic predisposition led to adolescent nicotine addiction and dependence as adults. It was found that those with a high-risk genetic profile who had tried smoking as teenagers were likelier to develop a habit in adulthood, while those with a low-risk profile were less apt to smoke as adults, even if they had in adolescence. Lead author of the study, Dan Belsky, notes, “(Genetics) didn’t predict who tried cigarettes, but they did tell you who among those that did try a cigarette – who got hooked.”
There’s clearly an undeniable link between genetic factors and smoking habits, but exactly what genes contribute to the development of this addiction? Although tobacco usage tendencies cannot be attributed to a single gene, a few genes have been noted in association with nicotine addiction. For example, variations in the gene responsible for the metabolism of nicotine and those related to dopamine signaling have been associated with heavy tobacco use.
Additionally, research suggests a correlation with a variant of the gene CHRNA5, indicating that this genetic variant may significantly increase the likelihood of developing a tobacco addiction. A 2014 study found that individuals who possess this variant have a much more enjoyable experience with cigarettes since this gene reduces tobacco’s unpleasant effects.
Something else to consider is the effect of heavy smoking on the area of the brain known as the habenula. This region is known as the brain’s emotional center and is associated with feelings of anxiety, fear, reward, aversion, avoidance, and related behaviors. Damage to the neurons in this part of the brain can result in intense negative feelings and emotions. One may attempt to soothe these unpleasant feelings by indulging in more nicotine, leading to addictive tobacco smoking.
Although many scientists and researchers have found a genetic link contributing to nicotine addiction, one must also consider the impact and role of environmental factors. Sociocultural influences play a significant role in the development of smoking habits among both adults and adolescents. For example, teens are more likely to try cigarettes if their peers, parents, or siblings smoke. Negative family relationships may also lead to adolescent smoking habits that can carry over into adulthood.
In addition, peer pressure, media, and advertising may contribute to the development of smoking habits. Certain social situations, TV shows, and movies tend to glamorize smoking, portraying it as cool or rebellious. This social pressure can fuel adolescents’ and adults’ desire to conform, contributing to widespread nicotine addiction.
Regardless of the cause of smoking behaviors, it is a harmful habit that can bring deadly consequences. Smoking can bring adverse effects to almost every organ in one’s body, with an increased risk of cancer being one of the most significant risk factors. For those looking to combat the negative effects of nicotine, a comprehensive detox regimen and exercise can help speed up the process.
In conclusion, the debate of whether or not smoking habits are influenced by genetics is complex and ongoing. Research suggests a strong correlation between smoking initiation and genetic factors, but more remains to be uncovered. In addition to the heritability of smoking habits, one must also consider the impact of environmental and sociocultural influences.