The Chemical Imbalance Theory
We’ve all heard of the chemical imbalance. What fewer are familiar with is the chemical imbalance theory. The concept has been so well embraced and often repeated that somewhere along the line people have dropped a critical part — that it’s only a theory — and a half theory at that.
The problem with the chemical imbalance theory is that, like so many others in biological psychiatry, it was reverse engineered. From a 2005 study published by Jeffery LaCasse and Jonathan Leo regarding SSRIs being marketed based on the unfounded theory:
In 1965, Joseph Schildkraut put forth the hypothesis that depression was associated with low levels of norepinephrine, and later researchers theorized that serotonin was the neurotransmitter of interest. In subsequent years, there were numerous attempts to identify reproducible neurochemical alterations in the nervous systems of patients diagnosed with depression. For instance, researchers compared levels of serotonin metabolites in the cerebrospinal fluid of clinically depressed suicidal patients to controls, but the primary literature is mixed and plagued with methodological difficulties such as very small sample sizes and uncontrolled confounding variables… Attempts were also made to induce depression by depleting serotonin levels, but these experiments reaped no consistent results. Likewise, researchers found that huge increases in brain serotonin, arrived at by administering high-dose L-tryptophan, were ineffective at relieving depression.
Researchers didn’t find an imbalance and devise a means of correcting it, they found a drug that, to some extent, had the desired effect and built a theory around how it might work. Never able to have consistent, measurable or reproducible results, the only constants in the chemical imbalance theory since its inception have been greater acceptance and increasing development and sales of selective serotonin reuptake inhibitors (SSRI). With direct-to-consumer advertising from pharmaceutical companies made easier in 1997 with the FDA conveniently loosening its ad guidelines at precisely the time when SSRIs had generated a more than substantial buzz, Pharma’s tv marketing machine went into overdrive, touting themselves as purveyors of chemical cures for known biological illness. With careful wording and lax guidelines, you can fairly easily tip-toe around the fact that the biological component to depression is just a shaky theory.
It is important to question how these drugs come into prominence and what role media and marketing play in that process. Even if we are skeptical of an ad blitz from pharmaceutical companies, many tend to see the news media as having some air of legitimacy, even more then than now. Having mentioned the almighty chemical imbalance in various ways for any number of stories, the news media supports it as legitimate scientific knowledge having very little push from anyone to verify it as such.
Building on the 2005 study, FSU doctoral candidate Jeffrey LaCasse and Jonathan Leo, a neuroanatomy professor at Lincoln Memorial University, shifted their focus to the news media’s portrayal of the chemical imbalance theory. They spent a year between 2006 and 2007 scouring the news. When a reporter mentioned chemical imbalance, typically as fact not theory, they contacted the news outlet and requested supporting information. None could be found. From an article in Medical News Today:
“Several reporters, psychiatrists and a drug company responded to the researchers’ requests, but Lacasse and Leo said they did not provide documentation that supported the chemical imbalance theory…
…there are few scientists who will rise to its defense, and some prominent psychiatrists publicly acknowledge that the serotonin hypothesis is more metaphor than fact…when asked for evidence, reporters were unable to cite peer-reviewed primary articles in support of the theory.
Moreover, the researchers said, several of the responses received from reporters seem to suggest a fundamental misunderstanding of the theory’s scientific status. The “Diagnostic and Statistical Manual of Mental Disorders,” which almost all psychiatrists use to diagnose and treat their patients, clearly states that the cause of depression and anxiety is unknown, according to Lacasse and Leo. “
So we have direct-to-consumer advertising selling the unsubstantiated claim of a chemical imbalance and its chemical correction all wrapped up in a package of sympathy and healing while the FDA allows them to play down the side effects and the news media offers free advertising by way of promoting the chemical imbalance myth unquestioningly — and no one seems too concerned that none of this is the result of objective scientific research. In addition, based on the reputation of the chemical imbalance, many other biological roots have been purported without proof and accepted without reservation by the public such as ADHD and bipolar disorder.
If an industry is prepared to make such claims, especially when targeting people who are arguably at their worst and weakest points in life, the burden of proof should fall upon that industry and then upon anyone who administers drugs bearing the names of the companies that comprise that industry. Failure to demand something as fundamental as proof of the existence of the problem they claim to correct is endorsement of shady business of the highest order. I know of no other establishment under the guise of medicine of which so little evidence is expected. If you claim to be able to cure a child’s cancer, that cancer must first be shown to exist. How is it that that level of certainty is not expected, much less demanded when tackling something as complex as the human brain?