May 13, 2024

How should we think and talk about mental health?

Article 1: Depression and the chemical imbalance myth

This is the first article in a new column written by Hans Schroder, Ph.D.


The history of the “chemical imbalance” phrase

Have you ever heard depression described as a “chemical imbalance?” Well, if you have, you’re not alone! A survey in 2007 found that over 90% of the participants surveyed had heard of this explanation. The chemical imbalance explanation suggests that depression and other mental health problems are related to an abnormal level of brain chemicals called neurotransmitters. Depression, in particular, is often talked about as “not enough serotonin.”

The specific term “chemical imbalance” was most popularized by pharmaceutical marketing and advertisements for antidepressants. The phrase was influential for several reasons and was adopted by several anti-stigma campaigns and public health efforts to encourage the public to acknowledge depression as a legitimate condition worthy of attention and treatment. While it is certainly a popular message, we now know that the actual neurobiology of depression is incredibly complicated and not simply a chemical imbalance of any sort. Research actually suggests that people with and without depression have similar levels of serotonin, and any differences between these populations is very complicated. In fact, it’s very hard to even measure serotonin and other neurotransmitters in live humans, and there are no established “normal” or “healthy” levels of any brain chemical. So, the “chemical imbalance” should now be considered a myth.


The psychological impacts of thinking about depression as a chemical imbalance

My research is not focused on the actual neurobiology of depression, but rather on people’s beliefs and reactions to messages about depression being a chemical imbalance. It turns out there is a lot of research in this area, and we have a few solid takeaways. There are both benefits and consequences of thinking about depression as the result of a biological or genetic abnormality, like a chemical imbalance.

In terms of positives, when people view depression as a chemical imbalance or as a genetic disease, they have less blame for having depression. This is important because when we’re depressed, we tend to blame ourselves for lots of things, even for being depressed in the first place. Second, when people view depression as being biochemically caused, they tend to think it is more “real” –  and we know that validating someone’s suffering is crucial for recovery.

However, research has shown several downsides to believing that depression is biologically-based. For example, these so-called biogenetic beliefs lead to greater social distance beliefs – wanting to be further away from individuals with mental illness – and greater perceived dangerousness (perceiving that someone with a mental health disorder is dangerous). In these ways, the chemical imbalance belief can increase stigmatizing attitudes.

Finally, believing that depression is due to a chemical imbalance or genetic deficiency is related to less hope for recovery, particularly with psychotherapy [read more herehere and here]. We think that one of the reasons this happens is that people feel they have less control over their recovery when depression is thought to be caused by biological, chemical, or genetic factors. For instance, in one study we conducted among patients attending a psychiatric hospital, patients who believed in the chemical imbalance explanation of depression actually had more depression by the end of treatment.



When people ask me about the neurobiology of depression, I tell them the truth. I say, “it’s really complicated – it’s certainly not a simple chemical imbalance – and we’re working on it.” I also make sure to let them know that just because something may be related to biology does not mean we have no control in our efforts to overcome depression. I let patients know that depression can be treated with a wide variety of interventions including exercise, lifestyle changes, psychotherapy, and medications. Notably, this does not mean that medications are not helpful. Medications can still play an important role in someone’s recovery from depression.

In a subsequent column I’ll be talking about some more of my research that presents an alternative framework for thinking and talking about depression. Stay tuned!


About the author:
Hans Schroder, Ph.D.

Dr. Schroder’s research focuses on how people think and talk about mental health. He studies common explanations such as the “chemical imbalance” narrative and how people interpret such messages. He also studies alternative frameworks for understanding mental health that may promote less stigma and more hope for recovery.