On Slate Star Codex, psychiatrist Scott Alexander asserts that the now widely discredited notion that depression is caused by a serotonin deficiency “was never taken seriously by mainstream psychiatry” and was never promoted by psychiatrists or pharmaceutical companies. He further suggests that no one at Mad in America has evidence that they did promote it.
Alexander’s post was a response to a recent article in iO9, exploring the rise and fall of the low-serotonin theory of depression.
On Critical Psychiatry, Duncan Double responds to Alexander’s post, noting that at the very least “there’s no doubt that many people have been taken in by the theory.” Duncan adds that many psychiatrists and pharmaceutical companies alike have confused or misled the public with chemical imbalance theories of various kinds, because the public often doesn’t realize that “the ‘chemicals in depression’ may not be much different from those that create normal feelings. It may not make much sense to view depression as a neurochemical disorder.”
For his part, Alexander argues that the notion that psychiatrists once promoted the idea of low serotonin as a cause of depression and Selective Serotonin Reuptake Inhibitors (SSRIs) as proper treatment for that deficiency is all simply a false “narrative” invented by “antipsychiatry” activists. These activists then “frame it as ‘proof’ that psychiatrists are drug company shills who were deceiving the public.” Alexander points to quotes of American Psychiatric Association officials in a post by MIA Blogger Philip Hickey, and notes that none of the quotes specifically describe a low-serotonin explanation for depression. The Hickey post cited is not actually about that topic, but about the promotion of the phrase “chemical imbalance”; nevertheless, Alexander broadly refers to Hickey and all of Mad in America as “antipsychiatry”, and he then writes, “If the antipsychiatry community had quotes of APA officials saying it’s all serotonin deficiency, don’t you think they would have used them?” Alexander argues, “The idea that depression is a drop-dead simple serotonin deficiency was never taken seriously by mainstream psychiatry.”
There seems to be a lot of evidence to the contrary still today readily available even on the web, though. For example, a 2004 Washington University in St. Louis press release, about a study published in Biological Psychiatry, states that the “brain’s serotonin receptors” are “at abnormally low levels in depressed people” and that antidepressants “work by increasing serotonin levels in the brain.” And there is prominent psychiatrist Richard Friedman writing in the New York Times in 2007 that psychiatrists were soon going to be able to conduct “a simple blood test” to determine “what biological type of depression” a person had and then treat them with the right drug. “For example,” writes Friedman, “some depressed patients who have abnormally low levels of serotonin respond to S.S.R.I.’s, which relieve depression, in part, by flooding the brain with serotonin.”
There’s also a lot of evidence that the low-serotonin theory of depression is still today being taken seriously by mainstream psychiatry and is still being promoted to the public.
A current University of Bristol public education website on depression explains that, “Low serotonin levels are believed to be the cause of many cases of mild to severe depression(.)”
A current Harvard Medical School special health report, “Understanding Depression”, explains that, “Research supports the idea that some depressed people have reduced serotonin transmission. Low levels of a serotonin byproduct have been linked to a higher risk for suicide.”
And WebMD‘s “Depression Center” states that, “There are many researchers who believe that an imbalance in serotonin levels may influence mood in a way that leads to depression. Possible problems include low brain cell production of serotonin, a lack of receptor sites able to receive the serotonin that is made… According to Princeton neuroscientist Barry Jacobs… common antidepressant medications known as SSRIs, which are designed to boost serotonin levels, help kick off the production of new brain cells, which in turn allows the depression to lift.”
And if the theory was never taken seriously and isn’t being taken seriously, no one has apparently told the National Academy of Sciences or two news media outlets with expert psychiatric editorial boards yet. Psychiatry Advisor‘s February 12, 2015 headline for a report about a Duke University study is, “Serotonin Deficiency May Up Depression Risk.” Psychiatry Advisor explains that, “(m)ice with normal serotonin levels, the control group, did not demonstrate depression symptoms a week after the social stress, while the serotonin-deficient rodents did(.)” The study, appearing in the Proceedings of the National Academy of Sciences, states that, serotonin deficiency has been “implicated in the etiology of depression” though a cause-effect relationship has not yet been “formally established.” The researchers write that their results, “provide additional insight into the serotonin deficiency hypothesis of depression.” Medical News Today headline their report on it even more strongly: “Mouse study finds that serotonin deficiency does increase depression risk.” (Medical News Today notes in passing that an earlier, somewhat similar study by a different team came to the exact opposite findings.)
MIA Bloggers Jonathan Leo and Jeffrey Lacasse explore the whole topic in a 2005 PLoS Medicine article, “Serotonin and Depression: A Disconnect between the Advertisements and the Scientific Literature,” and in a 2007 article in Society titled, “The Media and the Chemical Imbalance Theory of Depression.” And in two 2012 posts on Mad in America, Leo and Lacasse argue that most serious psychiatric researchers did indeed know all along that there was no evidence that low serotonin caused depression, even as the media and public over decades became ever more convinced that it did. However, for Leo and Lacasse those facts prompt a different question than they do for Alexander; namely, Leo and Lacasse ask where the historical evidence is of prominent psychiatric association officials making concerted efforts to stop the public from believing serotonin deficiencies could cause depression. “(I)f the Psychiatry Community knew all along that the theory was not true, then why did they not clarify this issue for the general public?” write Leo and Lacasse. “Why did the professional societies not publicly set the record straight?” Leo and Lacasse then describe NPR interviews with psychiatrists who admit that they are still today telling patients “that serotonin imbalance causes depression, even though they know this isn’t the case.”
No one should believe the chemical imbalance theory (Critical Psychiatry, April 7, 2015)
Chemical Imbalance (Slate Star Codex, April 5, 2015)
The Most Popular Antidepressants Are Based On An Outdated Theory [UPDATED] (iO9, April 1, 2015)
Psychiatry DID Promote the Chemical Imbalance Theory (Mad in America, June 6, 2014)
Brain’s serotonin receptors at abnormally low levels in depressed people (Washington University in St. Louis press release, May 10, 2004)
On the Horizon, Personalized Depression Drugs (New York Times, June 19, 2007)
Depression (University of Bristol, accessed April 11, 2015)
What causes depression? (excerpt from Understanding Depression, Harvard Medical School, accessed April 11, 2015)
Depression Health Center — Serotonin: 9 Questions and Answers (WebMD, accessed April 11, 2015)
Serotonin Deficiency May Up Depression Risk (Psychiatry Advisor, February 12, 2015)
Mouse study finds that serotonin deficiency does increase depression risk (Medical News Today, February 10, 2015)
Sachs, Benjamin D., Jason R. Ni, and Marc G. Caron. “Brain 5-HT Deficiency Increases Stress Vulnerability and Impairs Antidepressant Responses Following Psychosocial Stress.” Proceedings of the National Academy of Sciences 112, no. 8 (February 24, 2015): 2557–62. doi:10.1073/pnas.1416866112. (Abstract)
Leo, Jonathan, and Jeffrey R. Lacasse. “The Media and the Chemical Imbalance Theory of Depression.” Society 45, no. 1 (November 28, 2007): 35–45. doi:10.1007/s12115-007-9047-3. (Full text)
Lacasse, Jeffrey R, and Jonathan Leo. “Serotonin and Depression: A Disconnect between the Advertisements and the Scientific Literature.” PLoS Med 2, no. 12 (November 8, 2005): e392. doi:10.1371/journal.pmed.0020392. (Full text)
Psychiatry’s Grand Confession (Mad in America, January 23, 2012)
Revising the History of the Serotonin Theory of Depression? (Mad in America, January 29, 2012)
What is Serotonin and Signs of Serotonin Deficiency? (Health Ambition)