In media interviews and public appearances, there almost always comes a point when I tell people that the chemical imbalance theory of depression is a myth. I generally add that I mean “myth” in the best way possible: a powerful explanation of a complicated and disturbing phenomenon, but one that is not necessarily true in the sense that we expect scientific explanations to be true. I explain that the credibility of the myth hinges on a faulty logic: People take antidepressants and feel better. Antidepressants increase the availability of serotonin. Therefore a lack of serotonin was the cause of feeling bad. That’s a post hoc fallacy at best, but it is not too simplistic to say that this is the main source of the myth.
My comments are often met with incredulity, which makes sense, given how widespread this myth is, and given its role as a linchpin in the depression industry. After all, how many people are taking antidepressants because they have been told that they are suffering from a chemical imbalance that the drugs will rectify in the same way that insulin does for diabetes? And the corollary: that if you don’t take the drug, it will be like leaving diabetes untreated. So my comment is discomfiting and hard to believe. I generally acknowledge this and then suggest that people buy Manufacturing Depression if they want to get the whole story. Never pass up an opportunity for a plug.
The question that hangs in the air in this discussion is how it is possible that there can be such a disconnect between what doctors know and what they tell the public. That is a hard one to explain without resorting to conspiracy theories or attributing bad faith to doctors. I don’t like either of those explanations, and I am sure that neither does justice to the phenomenon. But so long as doctors say one thing to their colleagues and another to the public, the question looms. So I was pleased to see in today’s New York Times an article by Richard Friedman, a professor at Weill Cornell Medical College in New York City, and a frequent contributor to the Times. Friedman is anything but a psychiatric renegade, and here is what he says about the chemical imbalance theory:
Knowing how a drug works in the brain doesn’t necessarily reveal the cause of the illness. For example, just because an S.S.R.I. antidepressant increases serotonin in the brain and improves mood, that does not mean that serotonin deficiency is the cause of the disease; many depressed patients get better with medications that have no effect on serotonin.
So there you have it. Right from the horse’s mouth.
(One thing Friedman doesn’t mention: that many depressed patients get better with no medication at all.)