Is Addiction Hereditary: The Science Behind Addiction

Addiction is a disease, and many diseases are hereditary. But addiction is also behavior-based, which makes it more complex to study than, say, sickle cell anemia.

To fully understand is addiction hereditary or not, we have to look at the science of nature vs. nurture. Then we’ll look at the statistics of children of addicts and see what that science tells us.

In essence, addiction is both genetic and behavioral based. Here’s how that paradox works out based on the evidence we have and what we know about the human brain.

What is Addiction, Biologically Speaking?

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Your brain is like a pharmacy. It needs and runs on chemicals to do all sorts of processes. Some of these processes need electro-chemical impulses, which are what send messages from one part of the brain to another.

Other parts of your brain use neurochemicals to control your behavior. And you likely already know this. Think back to elementary school when your teacher used to put gold stars on your papers.

That made you feel good, right? You did something worth rewarding and then you got a reward. If we think of your brain as the homework/paper you wrote, dopamine is the gold star.

Dopamine is the reward chemical, it gives us that little boost that makes us feel like we did a good job, or feel happy. And it’s also a major aspect of what leads to addiction.

Drugs and Dopamine

Humans want to be happy. It’s written into the US constitution, that we have the right to pursue happiness.

But not all of us lead lives where we can make that happiness organically or find it in our communities. Or maybe we can, but something else in our brains is off and we don’t process the happiness we have.

That’s where drugs come in. Almost every recreational drug (and some pharmaceuticals) have an effect on dopamine. They make their levels shoot up, which is why people feel good when they’re high.

In the case of some drugs, like heroin, some people say that they never feel that good (after quitting) ever again. Drugs are heavy hitters when it comes to dopamine levels.

You could almost think of your dopamine levels as one of those “how hard can you hit this” games at the carnival. The drug slams your dopamine way up to the top of the game, and it gets stuck there.

Your daily activities and other happiness factors can never hit with the same strength. That means there’s a gap in what your brain expects to get in dopamine, and what daily living provides.

The Addiction Cycle

So – now imagine that situation over and over again. You keep taking drugs and your brain experiences higher and higher levels of dopamine. Eventually, the drugs are supplying your brain with so much dopamine that your brain says “I don’t need to make my own anymore”.

Then when the person comes down off of drugs, they feel awful. Their brains are no longer making dopamine, and don’t have the ability to make as much dopamine as the drugs have it used to.

So to feel okay again, the person does the drug again. Starting the cycle over, as the dopamine stores get lower and the brain gets lazier. It’s called a positive feedback loop.

Nature vs. Nurture in the Brain

Now let’s shift to the idea of something being hereditary. As scientists see it right now, about 50% of who we are is fixed at birth (from genetics) and the other half is shaped by our environments.

Now if someone has some genetic history of addiction but they’re raised in a responsible family and taught about safe/no drug use, the “nurture” 50% can win out. They may never have issues with addiction.

But the opposite is true as well. If someone has a genetic history of addiction and are brought up in a household where addiction is either obvious or obvious but ignored, that person has almost a 100% chance of becoming an addict.

Actually, if you look at the science, children of addicts (mostly biological but some adopted) are 8 times more likely to become addicts.

So that would prove that addiction is hereditary, right? Not quite.

There are still children who are born into a line of addicts and raised by addicts, that stay sober (or use responsibly) their entire lives. And we don’t know why.

Twins in Addiction Studies

A lot of studies are done on twins, in the nature-nurture debate, since they have the same genetic material. If both twins are adopted separately, one could end up an addict in a non-addiction household and the other could end up fine.

That happens about 40% of the time.

That’s where the science runs out – we don’t know why this happens. One idea would be that one twin got more of the gene where addiction lives, but that’s not true – identical twins have the same DNA.

The other 50-60% of the time, if one twin is an addict, there’s a high chance (the percentage above) that they’ll be an addict too.

The best form of explanation we have for these differences is the nurture argument.

If 50% of addiction is genetic, as shown by most twins, that means 50% of it is nurture, taught or behavioral based.

In the same twin study, the researchers determined that the twins that didn’t develop an addiction had better coping skills. They could deal with stress or uncomfortable situations better than the addicted twin.

Why? We assume the healthy twin learned that from their environment, but that’s not always true.

Hence we get back to the question, why are some children who are raised by addicts never addicts at all? They have both nature and nurture pushing them towards addiction, yet they’re able to resist.

It’s the nature/nurture addiction paradox.

What to Do if You’re the Child of an Addict

If you’re the child of an addict, you need to know that the way you process or look at drugs/alcohol will never be the same as someone without addiction in their family.

While that non-addiction prone person may binge drink in social situations and be fine later, that’s not necessarily the case for you. It’s unfair and you did nothing to deserve it, but you have to carefully consider the consequences of your actions.

The safest bet would be to avoid substances altogether. You already know that your body could use your biology against you if you partake.

But 100% abstinence isn’t reasonable, in most situations. Which would lead us to encourage you to strengthen your other 50% – your nurture.

If your parents are active addicts, you’re not going to learn these coping skills from them. You may have to seek out therapy on your own and make teaching yourself a goal.

Setting limits with yourself and with your therapist can help you avoid the addiction brain cycle. But still – there’s a chance that you could have those coping skills and become an addict.

It’s really a toss-up – and we wish we could tell you why.

If You’re an Addict and a Parent

Being a parent is a job and addiction is a disease. Doing a good job at your job with a disease is hard. We absolutely get that and we commend you for reading this article – because it means you’re trying.

If you’re worried about passing your addiction onto your child, you may need to work on yourself before you work on teaching them.

You, too, may need to go to therapy/drug rehab and work on those coping skills and self-control factors. It may mean that you take doctor-prescribed medications to get your dopamine back to a healthy level.

Only when you’re healthy can you show your children how to be healthy. You have to be honest with them about your struggles, as embarrassing as it may seem.

They need to know what they’re up against, and you need to build that nurture 50% up as strong as possible, to give them a chance of overcoming their biology.

It’s going to be hard work and a lifelong battle. Remember that kids will do what you do and learn from your every movement – even when you think they’re not watching.

But that’s a good thing. If they see you investing in yourself and taking time to face your problems, they’ll learn they can do the same.

If you want to learn more about how seeing = learning and doing, read about mirror neurons.