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Thursday, May 26, 2022

Do You Still Believe in the “Chemical Imbalance Theory of Mental Illness”?

Bruce Levine
Originally published 29 APR 22

Here are two excerpts:

If you knew that psychiatric drugs—similar to other psychotropic substances such as marijuana and alcohol—merely “take the edge off” rather than correct a chemical imbalances, would you be more hesitant about using them, and more reluctant to give them to your children? Drug companies certainly believe you would be less inclined if you knew the truth, and that is why we were early on flooded with commercials about how antidepressants “work to correct this imbalance.”

So, when exactly did psychiatry discard its chemical imbalance theory? While researchers began jettisoning it by the 1990s, one of psychiatry’s first loud rejections was in 2011, when psychiatrist Ronald Pies, Editor-in-Chief Emeritus of the Psychiatric Times, stated: “In truth, the ‘chemical imbalance’ notion was always a kind of urban legend—never a theory seriously propounded by well-informed psychiatrists.” Pies is not the highest-ranking psychiatrist to acknowledge the invalidity of the chemical imbalance theory.

Thomas Insel was the NIMH director from 2002 to 2015, and in his recently published book, Healing (2022), he notes, “The idea of mental illness as a ‘chemical imbalance’ has now given way to mental illnesses as ‘connectional’ or brain circuit disorders.” While this latest “brain circuit disorder” theory remains controversial, it is now consensus at the highest levels of psychiatry that the chemical imbalance theory is invalid.

The jettisoning of the chemical imbalance theory should have been uncontroversial twenty-five years ago, when it became clear to research scientists that it was a disproved hypothesis. In Blaming the Brain (1998), Elliot Valenstein, professor emeritus of psychology and neuroscience at the University of Michigan, detailed research showing that it is just as likely for people with normal serotonin levels to feel depressed as it is for people with abnormal serotonin levels, and that it is just as likely for people with abnormally high serotonin levels to feel depressed as it is for people with abnormally low serotonin levels. Valenstein concluded, “Furthermore, there is no convincing evidence that depressed people have a serotonin or norepinephrine deficiency.” But how many Americans heard about this?


Apparently, authorities at the highest levels have long known that the chemical imbalance theory was a disproven hypothesis, but they have viewed it as a useful “noble lie” to encourage medication use.

If you took SSRI antidepressants believing that these drugs helped correct a chemical imbalance, how does it feel to learn that this theory has long been disproven? Will this affect your trust of current and future claims by psychiatry? Were you prescribed an antidepressant not from a psychiatrist but from your primary care physician, and will this make you anxious about trusting all healthcare authorities?