AUG 20, 2019 8:44 AM PDT

What Causes Addiction?

WRITTEN BY: Annie Lennon

From nicotine to heroin, addiction is thought to be a reactive behavior to certain substances with addictive qualities. And so, convention has it that the best way to avoid addiction is to simply avoid them. But is this really the case? How else may addiction happen? 

It is difficult to pinpoint an isolated cause for addictive behaviors. In fact, it seems that they arise from a mosaic of different traits, including those from our genes and environmental factors. Although certain substances, such as nicotine, are known to be addictive, researchers have found that genetic traits may increase one’s likelihood of addiction to them. For example, a certain variant of the CHRNA5 gene can double one’s likelihood of developing a nicotine addiction, as it essentially softens nictotine’s negative effects, thus making it more pleasant to ingest than with other variants of the same gene (Fowler: 2014). 

Likewise, certain genes are also known to reduce one’s risk of developing an addiction. For example, a study of over 4,500 East Asian people found that those with a specific variant of the ALDH2 gene are nine times less likely to develop abusive drinking habits than those with other variants. This comes as this variant disables one’s ability to metabolise alcohol into acetate from the toxin, acetaldehyde. The buildup of this toxin in the body then causes nausea and general feelings of discomfort, thus discouraging the person from further drinking (Luczak: 2006). 

At this point, it is worthwhile seeing how environmental factors key in too. Between 1979 and 1992, a study found that the percentage of people who had this version of the ALDH2 gene and displayed abusive drinking habits increased from 2.5% to 13% (Ray: 2016). This is thought to have happened due to the introduction of a heavy drinking culture among Japanese businessmen, as well as stress from surmounting economic pressures as the economy began to weaken (Lennon: 2019). Thus, although genetic factors seem to influence one’s likelihood of developing addictive behaviors, their likelihood of manifesting seems to be closely interlinked with environmental triggers. 

Looking closer at environmental triggers, in the book “Chasing the Scream”, Johann Hari summises that addiction is caused by a lack of connection to one’s environment, as opposed to other factors. To make his point, he cites the “Rat Park” experiment. Conducted in the 1970’s, the experiment is famous for observing how, when left alone in cages in unhealthy living conditions with a bottle of plain water and a bottle of heroin-infused water, rats tended to prefer the water with heroin. Yet, when left in a cage with other rats and healthy living quarters, they preferred the plain water. From this experiment, and other examples, Hari says that addiction is therefore not just caused by chemical triggers, but how our environments make us susceptible to them. In this way, stressful environments are more likely to induce damaging behaviors, whereas more relaxed environments make them irrelevant (Hari: 2017). 

To conclude, addiction is caused by myriad factors beyond, although still including, addictive substances themselves. Thus, to understand the true causes of addiction, it is necessary to consider these factors taken together, as interlocking factors, rather than causes in isolation. After all, although an addictive behavior may be made more likely due to the presence of a certain gene, perhaps it was triggered by a certain environment. 


Sources 

 

Fowler, CD: Pub Med

Luczak, SE: Pub Med 

Ray, Lara A.: US National Library of Medicine 

Lennon, Annie: Labroots 

Hari, Johann: Huffpost 

About the Author
  • Annie Lennon is a writer whose work also appears in Medical News Today, Psych Central, Psychology Today, and other outlets. When she's not writing, she is COO of Xeurix, an HR startup that assesses jobfit from gamified workplace simulations.
You May Also Like
OCT 12, 2021
Clinical & Molecular DX
Tiny Fragments of RNA in the Blood Signal Dementia Risk
OCT 12, 2021
Tiny Fragments of RNA in the Blood Signal Dementia Risk
Scientists have discovered a novel biomarker in the blood that acts as an early warning sign for dementia: microRNA. The ...
OCT 21, 2021
Neuroscience
Do Childhood Psychotic-Like Experiences and Genetics Forecast Adult Psychosis?
OCT 21, 2021
Do Childhood Psychotic-Like Experiences and Genetics Forecast Adult Psychosis?
Researchers look to children experiencing psychotic-like experiences and genetics for leads to adult psychosis
NOV 02, 2021
Cell & Molecular Biology
Amino Acid Supplements May Prevent Neuronal Death & Dementia
NOV 02, 2021
Amino Acid Supplements May Prevent Neuronal Death & Dementia
Dementia is an umbrella term for several age-related disorders that can cause cognitive problems such as dysfunction in ...
NOV 04, 2021
Microbiology
Investigating the Gut Virome
NOV 04, 2021
Investigating the Gut Virome
The gut microbiome is a critical part of human health. Research has shown that many types of bacteria may reside there. ...
NOV 14, 2021
Microbiology
Beneficial Bacteria May Help Fight Ear Infections Caused by Bacterial Pathogens
NOV 14, 2021
Beneficial Bacteria May Help Fight Ear Infections Caused by Bacterial Pathogens
Researchers have identified bacteria that have the potential to fight infections that affect the middle ear and can caus ...
NOV 26, 2021
Coronavirus
Heavily Mutated COVID-19 B.1.1.529 Variant Emerges, WHO Names It Omicron
NOV 26, 2021
Heavily Mutated COVID-19 B.1.1.529 Variant Emerges, WHO Names It Omicron
On Thursday, November 2021, South African health officials announced that they had identified a new variant of the pande ...
Loading Comments...