The Epidemic of Mental Illness: Why?

From NYRB, source Marginal Revolution.

[a]fter Prozac came to market in 1987 and was intensively promoted as a corrective for a deficiency of serotonin in the brain. The number of people treated for depression tripled in the following ten years, and about 10 percent of Americans over age six now take antidepressants. The increased use of drugs to treat psychosis is even more dramatic. The new generation of antipsychotics, such as Risperdal, Zyprexa, and Seroquel, has replaced cholesterol-lowering agents as the top-selling class of drugs in the US.

[n]one of the three authors subscribes to the popular theory that mental illness is caused by a chemical imbalance in the brain.

But the main problem with the theory is that after decades of trying to prove it, researchers have still come up empty-handed. All three authors document the failure of scientists to find good evidence in its favor. Neurotransmitter function seems to be normal in people with mental illness before treatment.

For obvious reasons, drug companies make very sure that their positive studies are published in medical journals and doctors know about them, while the negative ones often languish unseen within the FDA, which regards them as proprietary and therefore confidential. This practice greatly biases the medical literature, medical education, and treatment decisions.

I would love to hear the views of medical anthropologists. Sometimes I wonder why we do not speak openly about this topic? It might have to do with evolutionary biology, society might consider weak somebody who suffers from depression and talks about it.