One in five people meet the threshold for clinical diagnosis of mental illness.

And the American Psychiatric Association is expanding its criteria for that label with the upcoming release of the fifth version of its Diagnostic and Statistical Manual of Mental Disorders, the "Bible" of mental health practitioners. Published for more than 60 years, the DSM describes everything from mild melancholy to full-blown delusions replete with auditory hallucinations.

However, some "psyches" and a number of would-be patients with Internet connections remain critical of the medicalization of normal ranges of thought and experience. Dr. Bernard Carroll, a former chairman of Duke University's psychiatry department, cites the 40-fold increase in bipolar disorder diagnoses among children during the past generation, as CNN reports.

"You've got all these young kids running around with this diagnosis, yet many of them have never, ever had a manic episode, which is the hallmark of bipolar disorder," said Carroll, now the scientific director of the Pacific Behavioral Research Foundation. "Many of these kids have never had anything other than irritability [and] yet they're exposed to anti-convulsants, anti-psychotic drugs, which have serious long-term side effects in the form of obesity, metabolic syndrome, diabetes and some movement disorders ... "

Such side-effects, Carroll said, can leave a kid permanently disfigured.

The "International DSM-5 Response Committee" is leading the blowback against the expansionary new manual, due for release May 20. The group says the APA is lowering diagnostic criteria, expanding the purview of psychiatric disorders into normal behavioral ranges and over-emphasizing medico-biological theories of mental disorder when evidence suggests multifactorial causes.

However, the APA defends the latest iteration of the manual as transparent and based solidly on science.

"All the good epidemiological studies unfortunately show that one in five people have a psychological disorder ...They're prevalent, they're just all over the place, and that's very disturbing to some people," says Dr. Carl Bell, director of public health and community psychiatry at the University of Illinois School of Medicine. "If you dig down into (the DSM-5), it's an extraordinarily complex document."

Other supporters of the new DSM V say the APA's vetting process has been supported by the Institute of Medicine in Washington D.C. and has involved more than 400 international scientists and 13 medical conferences with 18 months of independent review.

Among more controversial changes is the proposed "Disruptive Mood Dysregulation Disorder," a clinical diagnosis for children ages six to 18 who experience temper tantrums "grossly out of proportion in intensity or duration to the situation," as Slate reported. In defense the disorder, the APA said the new category should slow the growth in diagnoses for more serious conditions, such as the bipolar disorder -- the one that's increased by 4,000 percent.