It is no secret that psychedelic companies are making a move to overtake Selective Serotonin Reuptake Inhibitors (SSRIs) as the primary treatment for depression. So, when the Chemical Imbalance Theory came into question last year, many people in the industry were excited. Unfortunately, the scientists attempting to throw out the baby with the bathwater didn’t quite provide the whole picture. 

In July of last year, an umbrella review called into question the validity of the long-believed theory as to what causes depression. As a result, it essentially challenged the entire medical protocol system for treating depression. However, the review provided false, and even dangerous, information that was tainted by researcher bias. 

History of the Chemical Imbalance Theory & SSRIs

In order to grasp the significance of this, you first have to understand the history of the chemical imbalance theory and anti-depressant medications. 

Currently, around 85% of the public believes the chemical imbalance theory, which states that psychiatric conditions are caused by an imbalance of neurotransmitters in the brain, specifically serotonin. The theory gained popularity in the 1960s and was cemented as the leading hypothesis as to what causes depression when Prozac became the first SSRI to gain FDA approval in 1987. 

SSRIs prevent the brain from reabsorbing serotonin, which increases the amounts of it in the body. The fact that Prozac helped so many people feel better than they had before only served to confirm the chemical imbalance theory for many people. After all, if a chemical imbalance in the brain does not cause depression, then why would an increase in Serotonin help alleviate symptoms? 

The umbrella review of the chemical imbalance theory that came out in 2022 attempted to discredit this theory. It claimed that there is not enough evidence to support the hypothesis. It also aimed to discredit the efficacy of SSRIs. Since people tend to turn to psychedelics when traditional mental health treatments have failed them, the industry was quick to jump on board with the idea that current pharmaceutical tools for treating depression are based on a false premise. However, the umbrella review may not be as solid as many had hoped. 

Since its’ release, the review has been discredited by many prominent scientists in the psychiatric and neuropsychopharmacology fields due to author bias. The scientists who published it are known to “morally oppose biological evidence for psychiatric conditions,” said neuropsychopharmacologist Ryyan Zafar.

The review cherry-picked data that led to the conclusion that serotonin levels have no effect on depression, which is simply not true. That is not to say that low serotonin is the sole cause of depression— the research shows that isn’t true either. Nevertheless, serotonin does play a role in mental health. 

What Causes Depression?

Any respectable scientist will say that they don’t entirely know what causes depression. However, they do know more about the issue today than ever before.

Though we don’t have a complete picture of what causes depression, a recent study proved that people suffering from depression produce less serotonin than healthy individuals. It is true that up until recently, there was little evidence to prove the chemical imbalance theory. This study, out of Imperial College London, was the first-in-human study that gives evidence that people suffering from depression are serotonin depleted. 

So yes, serotonin does have a role in mental health. However, Rayyan Zafar explained that there are likely other factors at play. Neurotransmitters, including GABA, norepinephrine, and others, are believed to also affect depression, though more research is needed to confirm this. Recent research has also suggested that neuroplasticity may play a role in mental health issues, including depression, PTSD, and addiction. All of these health issues are multifaceted, which is why psychedelics may be a promising new pharmaceutical solution to mental health problems.

Psychedelics vs. SSRIs for Treating Depression

The introduction of SSRIs to the market did more than just offer a new drug to people suffering from depression; it revolutionized the pharmaceutical industry and the way people view mental health conditions. Prozac went far beyond just treating traditional depression. The company selling it began targeting issues that had not previously been seen as illnesses, such as PMS. This began an influx of new pharmaceutical drugs hitting the market to treat issues that had previously been considered wants and desires, not medical conditions in need of a pharmaceutical solution. This is not entirely unlike what psychedelics are doing. 

While psychedelics are being targeted to treat specific conditions, such as depression and PTSD, their potential reaches far beyond that. Back when Prozac hit the market, Dr. Peter Kramer believed that it had the potential to improve the lives of healthy individuals, in addition to those struggling with mental health issues.

Prozac may not have been the miracle drug that Dr. Kramer thought it could be. However, psychedelics could be. Many people have touted psychedelics for their ability to help improve creativity, clarity, and more. Yes, psychedelics have the potential to provide results far beyond what any drug currently available (legally) can do. 

SSRIs have a limited potential for several reasons. First of all, they often come with side effects that psychedelics do not. However, that does not mean that SSRIs don’t work at all. 

Some people find significant benefits from SSRIs, but there is still a place for psychedelics in the future of depression treatment. Rayyan Zafar believes that psychedelics may have the potential to outperform traditional anti-depressants in efficacy. Though he says, that is just speculation until phase III data is available. 

The truth is that the scientific community doesn’t entirely understand what causes psychiatric disorders. Rather than creating pharmaceutical drugs based on an understanding of what causes mental health issues, the industry has been finding drugs that seem to help these conditions and then basing theories about the cause of depression on how the drugs work. While many psychedelic supporters are critical of traditional psychiatric drugs for this reason, truthfully, the same thing is currently going on with psychedelics. 

There has been an increase in scientific research on how psychedelics work over the past decade, and it is clear that they have incredible potential for treating an array of health issues. However, scientists still don’t entirely understand why psychedelics are so effective. More research is needed to create a concrete understanding of what causes depression. But one thing is for sure— this is a complicated issue that affects a lot of people. 

Throwing around personal beliefs disguised as scientific facts, as happened in the umbrella review, has the potential to cause significant harm. False information could cause patients to turn against the medications and treatments that they rely on. Stating that scientists aren’t entirely sure what causes depression doesn’t exactly make for a click-bait article title. However, responsibility to people who are struggling with their mental health is far more important. After all, that is the premise on which the psychedelic industry is based.

Psychedelics can still transform mental health treatment without completely disregarding the drugs that have come before it. Psychedelics and SSRIs are both beneficial assets to scientists researching treatment for depression. They represent useful tools that can be used to better understand how the human brain works, which is still a bit of an anomaly.

SSRIs work by decreasing activity in the limbic system, which is responsible for emotions. They essentially numb emotions to make it easier to handle stressful situations. On the other hand, psychedelics work by increasing activity in the brain and promoting neuroplasticity. This difference is where there are some valid arguments for the use of psychedelics over traditional anti-depressants. One could say that numbing emotions is not a solution but just a bandaid. This is a belief that many people who have healed through psychedelics believe, though, of course, more research is needed to support this theory. 

Additionally, psychedelics are non-habit forming and have few side effects— unlike SSRIs. Initial studies also suggest that they have a higher rate of success. Promising or not, it is dangerous for people, especially scientists, to go around completely disregarding SSRIs. 

SSRIs do work for some people. And, whether they are as efficacious as psychedelics or not, it can be very challenging and even dangerous for patients to quit their medication. The psychedelic industry is full of people passionate about the transformative potential these medicines can offer. However, the industry has a responsibility not to disregard scientific evidence in favor of personal opinion. 

The chemical imbalance theory is an important part of a complicated picture of what causes depression. It is important to understand that scientists are only beginning to understand the very complex system that is the human psyche. Rather than getting caught up in clickbait articles that cater to personal beliefs, it is crucial for the psychedelic industry to stay grounded in truth, even if that truth gives way to uncertainty.