Is Addiction a Disease? The Great Debate

Is addiction a disease? What is addiction? This word gets thrown around frequently as we try to understand what it is that causes some people to continue abusing drugs and alcohol, even when it is ripping their lives apart. The United States leads the world in the number of deaths from overdoses, but addiction is not just an American problem (Lopez, 2017). According to the 2017 World Drug Report, nearly 30 million people worldwide suffer from substance abuse disorders (United Nations, n.d.). Many of these addicts struggle with more than one disorder at the same time, including multiple addictions or a mental illness diagnosis (Statistics, n.d.).

Addiction is nothing new, but there is disagreement on what actually causes it. It is a complicated problem that is influenced by many factors, including poverty, genetics, and the environments we live in. One of the greatest struggles that comes from this disagreement is how we should treat addiction.

Are addicts truly powerless against substance abuse? Is it simply a habit that has been deeply ingrained into their behavior – a really bad habit? Or, is does addiction come from a mix of brain changes, personal struggles, and poor coping skills?

Much of the controversy over addiction comes from differing definitions of what a disease really is. Scientists and researchers also interpret data about addiction differently, and come up with various conclusions. There are currently three main models or ways of looking at addiction: 1) addiction is a disease, 2) addiction is behavior and habits that are learned, and 3) addiction is a choice.

Before we discuss the arguments used in these three models, let’s talk about what we know happens in an addicted brain. Next, we’ll cover why there can be confusion when we label addiction a disease. Finally, we’ll summarize the three models of addiction and why there is disagreement surrounding them.

The Addicted Brain

At a very basic level, there are three main parts of the brain that are involved in addiction. These include the prefrontal cortex, the striatum, and the midbrain. The prefrontal cortex is in the front of your brain and helps you plan and make good decisions The striatum is located in the very middle of the brain and is responsible for motivation and goal setting. Finally, the midbrain lies just beneath the striatum and influences how we respond to events or situations.

Addictive behaviors seem to be part of a process that evolved over time into the human brain. When a person’s brain is stimulated by something pleasurable, maybe an image or the smell of a favorite food, the midbrain sends a rush of dopamine (a pleasure-inducing chemical) to the striatum. When the striatum is triggered by this dose of dopamine, it causes the person to start craving what they were thinking about. The more the person thinks about the craving, the more dopamine is released.

Here’s a simple example. Imagine you really, really like chocolate. At some point in your day you’re going along, running errands, and you happen to walk by a chocolate store. You see fresh fudge in the window display. This image of decadent, mouth-watering chocolate sends that charge of dopamine from your midbrain to your striatum. The next thing you know, you are seriously wanting that chocolate and can’t get it out of your mind. The more and more you daydream about the fudge, the more intense your cravings become.

Here’s the problem: the more your brain’s striatum and midbrain talk to each other with the help of dopamine, the less they are talking to and getting input from your prefrontal cortex. Maybe your craving becomes so strong that you forget that you were on a diet, or that getting a chocolaty treat will ruin your appetite for dinner. All you can think about is the fudge.

Let’s extend this image. Imagine you walk by that same chocolate store every single day after work. Each day, you end up stepping in and buying a piece of fudge. Before too long, you begin craving that fudge well before you come near the chocolate store. Instead, you start craving the fudge when you look at the clock and realize it is time to leave work. Your brain has begun tying together different cues with your chocolate cravings.

The same happens with addiction, only at a deeper level. The striatum and midbrain in an addict have very strong connections when a pleasurable trigger occurs, at the expense of the prefrontal cortex. So, when addicts are craving a drug or alcohol, they literally lose their capacity to think clearly and make the best decisions possible. Their good judgment gets hijacked by unconscious cues and craving mechanisms in their brains (Satel & Lilienfeld, 2014).

These triggering events and cravings create a feedback loop in the brain. An addict experiences something that makes them crave their addiction. Even if they try to ignore it, the cravings become stronger and stronger. Finally, the addict is compelled to use and feels satisfied for a time. However, it is just a matter of time before they have another triggering event that starts the craving cycle all over again (TedMed, 2016).

Different drugs affect the brain in unique ways, but they all generally work off of this loop that pushes them to act on cravings. A person may choose to use alcohol or drugs voluntarily at first. But, over time, the changes in the brain can decrease that person’s ability to resist future cravings. Free choice gradually becomes a compulsion to use.

The Nature of Disease

It is important to have a definition for what a disease is before we can decide if addiction is one. In reality, this is a difficult task and scientists often disagree on definitions. For example, is an illness a disease only if it comes from causes we have no control over? Can a disease also be something that results from our behaviors or lifestyle choices? Finally, is it still a disease even if symptoms go away just by stopping a behavior?

The ways in which we understand and describe diseases have changed over time. As advances are made in medicine and technology, we have come to a greater understanding about many illnesses. For example, at one time, homosexuality was considered to be a hormone imbalance, and so labeled a disease. The American Psychiatric Association changed its mind and took it off its list of diseases in 1974. Another example is osteoporosis. There was a time when osteoporosis was believed to be a normal part of aging. We now know that it not normal, and so the medical world calls it a disease (Scully, 2004).

The way we view disease is also influenced by our cultural settings and belief systems. Some people have suggested that Americans are especially fond of making everything a disease. Stanton Peele, an addiction psychologist, once remarked that Americans try to create a drug for everything. Our mindset is to try and “medicalize” all of our problems (Butler, 2006).

Interpretations of the Data

Quite a bit of research has been done over the last several decades looking at addiction and the addicted brain. In addiction, visual brain scans in people and animal experiments reveal that addictions do causes changes in the size of the brain and the way it works (What is Addiction, n.d.). The biggest arguments in this addiction debate are not about whether or not the research is true. Rather, they are center on disagreement about what a disease is and how we should interpret the science about addiction.

Three main models of addiction are briefly discussed here. Each talks about how using drugs and alcohol can create addictions, but they don’t necessarily go into detail about why people start using in the first place. In many cases, these underlying reasons a person tries a drug or alcohol can play a role in them developing addiction.

Learning Model of Addiction

Marc Lewis, a developmental psychologist, neuroscientist, and former addict himself strongly argues that addiction is not a true disease. He agrees that the scientific data and brain scans are clear that changes do occur in the brain during addiction. However, he suggests that there are multiple ways to interpret the results. In Lewis’ opinion, addiction is a matter of deep learning and habit formation (TedMed, 2016).

According to his theory, the feedback loop mentioned earlier causes people to develop strong habits. This happens through three things: 1) a person uses a drug or alcohol because of cravings, 2) the person feels relief and maybe pleasurable feelings as well, and 3) the person feels a sense of loss, shame or guilt. The brain learns that using the substance can help them avoid those bad feelings, and so it presents more cravings, and the cycle repeats itself. With every turning of this cycle, the habit becomes stronger and harder to overcome (Lewis, 2016).

Lewis and others who support this model believe the brain is just doing what the brain always tries to do: become more efficient and streamlined. This has been described through the pithy saying, “Neurons that fire together, wire together.” When behaviors are repeated and reinforced, new brain circuits are created.

Imagine brain circuits as train tracks for delivering messages and goods around the brain. In order to be more efficient and faster, the brain lays new tracks between the areas of the brain that are doing the most business, and maybe lets some of the older tracks fall into disrepair. The more often one set of tracks is used, the less likely the older tracks will be chosen for the job. Put simply, habits are created when the same tracks are used again and again by the brain because they are familiar and fast.

But Lewis doesn’t think this habit formation is a disease. He points out that the brain always changes when learning something, no matter what it is. The brain regularly adjusts its circuits (tracks) as needed. The brain then, is not broken or functioning improperly; it is just doing what it was designed to do. This has been shown through brain scans of people who practice meditation, or receive psychotherapy, or even drive taxis for a living and need to remember places and locations with quick recall (Lewis, 2016).

Despite the fact that he considers addiction a matter of deep learning and habit formation, Lewis doesn’t make light of addiction. In a 2015 interview in The Guardian, he said he believes that addiction is a socioeconomic problem combined with a “lack of care by the larger society for people who are suffering.” He recognizes that there is a lot of hard work required for addicts to become free from their addictions. Furthermore, when people are ready to leave their addictions, they need outside support and resources to help them get their feet underneath them once again (Davey, 2015).

Brain Disease Model of Addiction

Nora Volkow, longtime researcher and director of the National Institute on Drug Abuse, believes addiction is a disease because of the chronic effects it has on its victims. She agrees that learning and behavior patterns play a role in addiction forming. However, she believes addiction becomes a disease when addicts lose control over where or not they choose to use.

Addicts become helpless against their cravings, which is related to the changes caused by the drugs or alcohol to the brain (CBSNewsOnline, 2012).

In a 2016 issue of the New England Journal of Medicine, Volkow and her colleagues describe what happens in the body that cause this loss of control. A person uses a drug or alcohol and becomes intoxicated, experiencing a high or pleasurable feelings. These highs are created by a brain chemical mentioned earlier called dopamine. Repeated, strong shots of dopamine in the brain, Volkow says, influence behaviors in an unconscious way. Every time dopamine is released in response to a cue or craving, those behaviors become more ingrained as habits (Volkow, et al, 2016).

A second problem occurs when strong dopamine surges occur again and again: the brain stops responding to it as well as it did before. As a result, the addict needs more and more of the substance to get the same highs. This is referred to as tolerance.

Dopamine is naturally released in the healthy brain, and helps us feel pleasure or satisfaction. However, the constant dopamine releases from substance abuse really wear the brain out. It stops producing its normal amounts of dopamine, which can cause addicts to feel low or depressed. As a result, many addicts need to take drugs to stimulate the brain to release more dopamine – not so that they feel high, but just so they can feel normal once again (CBSNewsOnline, 2012).

Volkow says that the changes in the brain from addiction impact a person’s ability to think about consequences and make good choices. Referring to our earlier train track metaphor, this happens because the signaling tracks within the brain have started bypassing the prefrontal cortex. Instead, the strongest tracks go back and forth between the striatum and midbrain. The brain’s ability to use good judgment is hijacked.

This model points out several specific factors that define addiction as a disease. First, drugs and alcohol seem to cause changes in the brain, as seen in brain scans. Second, they cause an abnormal process in the body by leading to a decreased natural release of dopamine. Finally, all of these changes have long term effects, often well after addicts stop using. Symptoms can still appear months or even years after an addict becomes abstinent. It is these chronic, sometimes irreversible changes that leads Volkow to believe addiction is a disease (Volkow, 2012).

Supporters of this model also believe that calling addiction a disease has helped promote support for addicts. As science attempts to understand the underlying brain chemistry involved, many new medications that can reverse drug overdose, like naloxone, have been created. The mass of scientific research and data has also influenced the US healthcare system to change its approach towards addiction. The 2008 Paul Wellstone and Pete Domenici Mental Health Parity and Addiction Equity Act now requires medical insurance in the United States to cover addiction treatment. Many who hold to the brain disease model believe all of these factors have helped to remove the stigma associated with addiction (Volkow, 2015).

Choice Model of Addiction

Boston College and Harvard researcher Gene Heyman offers a third way of looking at addiction: addiction as voluntary choice. He argues there is only a small percentage of people in the overall population that actually become addicted. He also points out that approximately 75-80% of all addicts eventually kick their addictions by age 30. This usually happens because they develop goals that are more important to them than the desire to use, including legal or money concerns or the desire to be respected by family and friends.

Heyman doesn’t consider addiction a disease, but neither does he reduce it to a “simple” choice based on the addict’s morals or character. Rather, he describes it as voluntary behavior that is influenced by life circumstances. It is also related to the tendency of all humans to make dumb decisions or poor choices some of the time. If this weren’t true, he says, the self-help industry in this country would not be thriving like it is, where huge portions of the population are searching for ways to kick procrastination and other bad habits.

Addiction comes down to incentive, rewards, and the ability to delay instant gratification for long-term goals. The availability of good, alternative choices also seems to play a role in overcoming addiction. Addicts must believe they have options other than continuing in their addiction that make it worth letting that addiction go. Evidence for this is seen in the fact that many addicts come from backgrounds marked by abuse, minority status, or underprivileged socioeconomic status.

Heyman is convinced that the brain disease model of addiction doesn’t hold up when it comes to good research or logic, for several reasons. First, he points out that the brain scans used to “prove” addiction is a disease are limited and only suggest that brain changes are present with drug use. They don’t prove that the drugs themselves caused the changes. Next, if most addicts quit on their own without professional help, then logic follows that brain changes caused by drugs and alcohol are not enough to prevent them from changing their long term behaviors. Finally, Heyman says that the addicts in much of the research don’t represent all addicts as a whole. Instead, the research is based on a unique group he calls a “distinct minority.” These are the only the addicts that actually come to the clinic for help, or who aren’t likely to quit using because of other complicating factors (Heyman, 2013).

Why the Models of Addiction Matter

Some may wonder why these models for understanding addiction are even that important. Don’t we just need to give addicts tools to help them quit using? In reality, how we understand addiction influences treatment strategies and the ways in which society views addicts. The development of these models of addiction over time have helped educate people that addiction is not the result of poor character or bad morals.

Each of these models has brought important ideas to the table that color a broader picture of addiction. They help to continue thoughtful dialogue and debate between different branches of science. Instead of giving us simplistic reasons for addiction, each model discussed above admits that addiction is complex and requires hard work to overcome.

The models also seem to agree that initially, many drug and alcohol addictions begin with a voluntary choice to use a substance. However, why people choose to use and what happens in the body afterwards are both sources of disagreement. The brain science is clear, but there is not a clear consensus on what the data tells us about addiction.

Finally, although the conventional brain disease model of addiction is no longer accepted by everyone, it has attracted funding for brain imaging, genetics research, and drug development studies. Data from this brain research will no doubt be helpful in other areas of disease beyond addiction.


The struggle to understand the root causes of addiction is not a trivial matter. It will take time for science to fully get a handle on the complexities of this issue. How we think about addiction will also continue to influence healthcare, stigma surrounding addiction, and whether or not we consider addicts to be criminals.

It is crucial that we don’t reduce addiction to morality, character, or chemical imbalances. No matter what model we support, we must acknowledge that addiction is a complex issue that has overreaching effects into all areas of society. Each of the models presented above may disagree on the causes of addiction, but they each contribute to the conversation and lay the groundwork for improved addiction therapies and treatments in the future.



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