Antidepressants are the most consumed medication in the United States, yet the idea behind them—that mood disorders are caused by lack of serotonin or some other chemical imbalance—is unproven, Jarrett and many others say.
In truth no one knows what the “correct” levels for different neurotransmitters should be. . . . [V]arious studies have struggled to show consistently that serotonin function is lower in people who are depressed or anxious—this includes postmortem tests and measures of chemical levels in the cerebrospinal fluid of patients and healthy people. . . . [A]rtificially reducing people’s levels of serotonin doesn’t have a reliably depressing effect.
One drug that reduces serotonin—a “selective serotonin reuptake enhancer” (Prozac and other SSRIs are reuptake inhibitors)—is an effective antidepressant. Except for the most seriously depressed people, the SSRIs mostly seem to work because of the placebo effect. When I present this argument to my medicated friends, they say, “I’m fine with my placebo effect,” and I’m sympathetic. Advocates for the mentally ill believe that biological explanations make illness more acceptable. But as Jarrett points out, that may be another myth. A growing body of evidence suggests that biological explanations are stigmatizing, possibly because people tend to see such problems as less treatable.
Beyond the placebo effect, the currently popular antidepressants may work because they stimulate neurogenesis, the growth of new neurons. Researchers have stimulated neurogenesis in rats by giving them more exciting environments and challenging learning tasks. Stress and threats diminish neurogenesis in rats. Does this mean that the problem all along was your stifling or precarious job or marriage? There’s also evidence that the balance of microorganisms in your gut affects mood.
Temma Ehrenfeld, Gray Matters | The Weekly Standard.