If you are among the nearly 20 million Americans or countless individuals globally who have struggled with an addiction, it’s likely you have asked yourself why. 

Mankind has utilized psychoactive substances for religious, spiritual, and recreational purposes for millennia. The vast majority of human beings who consume alcohol and use drugs are able to moderate their use in a way that does not impact their lives and functioning to any great extent.

Others among us have walked a more difficult road. For some of us, the pull of drugs and alcohol is so strong that it becomes an all consuming force in our lives. But why can some of us enjoy a single drink on occasion, while others of us are compelled to consume alcohol to excess? Why can some of us safely take opioid painkillers as directed while others become ensnared in intractable dependency on drugs like Oxycontin and heroin? 

We have come a long way since the days when addiction was believed to be a purely moral failing that we should be able to overcome through hard work and will alone, but there is still a good deal of misunderstanding and disagreement about the mechanism of addiction and how to manage it. 

The Nature vs. Nurture Debate

The term “nature vs. nurture” is used to discuss many medical and mental health conditions when the origin of that condition is unknown. In other words, when we ask whether something is caused by “nature” or “nurture”, we are considering whether genetics and biology or environment had a greater effect on someone’s condition. 

The truth is, it isn’t always easy to parse whether nature or nurture is to blame, and in fact, it usually isn’t just one or the other. Biology and genetics interact with environmental factors like parenting, relationships, and trauma to create an effect. An emerging area of research called epigenetics even suggests that our DNA is affected by environmental factors not just before we’re born, but before we’re conceived. 

Like any health condition, there is debate over whether there is more nature or more nurture at play in those who become addicted.

Addiction and Genetics

Studies consistently show that genetics make up as much as half of a person’s risk of becoming addicted to drugs or alcohol, but can vary depending on the type of drug. For example, genes can make up as much as 75% of a person’s risk of becoming addicted to nicotine. 

It is important to note that there is not just one genetic marker that can indicate a person’s risk for developing an addiction. As many as 11 different genes may be involved in the development of addiction in an individual.

There are many ways in which the involved genes can lead to addiction. Genes can affect the way our bodies metabolize drugs and alcohol. They can determine the level of dopamine--a neurotransmitter responsible for generating feelings of pleasure and reward--present in our brains. Genes can even affect the way in which our brains process memory, affecting the ways in which we learn--or do not learn from our mistakes. 

This is to say nothing of the effect of epigenetics. Epigenetics refers to the way our environments affect the ways in which our DNA functions. You may have heard epigenetics talked about in the context of “gene expression”. In other words, epigenetics considers how genes can be “switched on” or “switched off” due to exposure to environmental stressors like toxic chemicals, stress, or drugs and alcohol.

So, how is the development of addiction affected by epigenetics?

While there are many ways in which the environment can affect our genes, early exposure to drugs and alcohol can alter our genes in ways that make us more vulnerable to addiction. Research has shown that repeated exposure to certain drugs can alter our DNA in ways that cause changes to the reward center of the brain. The reward center of our brain is what causes us to experience pleasure, and when it is not functioning optimally, cravings for more drugs or alcohol can arise. 

The role of genetics and biology in addiction is complicated, but knowing it plays a role can help put our struggles in perspective.

Addiction and Environment

While genetics play a major role in addiction, the effect of our environment can’t be underestimated. 

In many cases, we use drugs and alcohol as a means to cope with painful feelings, stress, anxiety, mood swings, or lack of motivation. While genetic factors can influence the means we use to cope, so can our upbringing. 

If you grew up in a home where the adults commonly used drugs or alcohol to cope with stress, you may have learned that this was an effective way to relieve anxiety. If you grew up in a home where your caregivers were permissive about your own use of drugs or alcohol, you may have been introduced to substance use early on in your development, which is a known risk factor for addiction. If your childhood or adolescence was marked by trauma and you were not offered effective mental health support, you may have found that drinking or drug use offered a distraction from your pain. 

Environmental risk factors for addiction include, but are not limited to:

• Poverty
• Community violence
• Social isolation
• Emotional or material neglect
• Physical, emotional or sexual abuse
• Pressure to perform academically
• Easy availability of drugs or alcohol

None of these factors alone can explain why someone develops an addiction. Whether someone becomes addicted to drugs or alcohol heavily depends on a confluence of factors. A person with a high genetic predisposition to addiction might grow up in a loving and supportive environment where all their needs are provided for, and avoid addiction entirely. Someone else might experience trauma and abuse, but never crave drugs or alcohol because they lack genetic markers for the disease. 

Reducing Addiction Risk

If you’re reading this, it may be because you have a family member who struggles with addiction, you are concerned about the risk of you or your children inheriting an addiction that has been passed through generations, or you’re simply wondering whether such a problem can be avoided. 

While there is no way to guarantee that any of us will avoid addiction altogether, it’s possible to mitigate some of the risk. 

If you are a child of parents who struggled with addiction, it might make sense to either abstain from drugs and alcohol altogether, or to be careful and conscious about how much you consume. Further, if your home was chaotic or you experienced abuse or neglect, it can help to process these experiences with a therapist. Finally, groups like Al-Anon and Alateen offer support for family members of people with addiction.

If you are concerned that your child is at risk for addiction because you or their other parent is in recovery or is actively using, there is a lot you can do. First and foremost, if you are still using, get help. The best thing you can do for your child is to prioritize your own health and wellbeing. 

Beyond that, you can educate your child in an age appropriate way about their potentially increased risk and the deleterious effects that addiction can have on our lives. You can support your child through difficult life events like the death of a loved one or the move to a new town. You can teach your child that taking care of their mental health should be a priority by enrolling them in therapy or support groups at an early age.

While we may never know exactly how addiction develops, the knowledge that we do have is powerful. Sobriety is hard, but the future is in our hands.