TORONTO - A man who spends two to four hours viewing Internet porn and masturbating as much as 12 times daily might have any number of labels pinned on him.

Beyond the lewd and lowbrow, however, is a polarizing term even among professionals: sex addict.

In an unusually public move this week, actor David Duchovny, best known for his role as FBI agent Fox Mulder in "The X-Files," claimed to be a sex addict and voluntarily admitted himself into a rehabilitation facility.

No details have been released as to what might exactly be ailing Duchovny, who currently stars on the sexually charged TV show "Californication."

Somebody who spends a lot of time and energy engaging in sexual activity either alone or with others -- and whose life is negatively impacted by that behaviour -- would be considered to have a sexual addiction, said psychologist Dennis Kalogeropoulos of the McGill University Health Centre.

"We can't just say if somebody masturbates 12 times a day, that's wrong," said Kalogeropoulos, who runs a sex and couple therapy service.

"If they take care of other things in their life, if they're physically and physiologically OK otherwise, we can't really say that."

Signs of dysfunction include students not studying for exams, or people at work sneaking off to the bathroom to masturbate in the middle of the day, Kalogeropoulos said. A craving for Internet porn, for example, might result in poor sexual relationships with partners or ruined careers.

Over the past five years or so, Kalogeropoulos said he's received a tremendous increase in referrals to his Montreal clinic, especially from young men with Internet porn habits.

But he admits the condition of sexual addiction is rife with controversy, and he is frustrated by the lack of academic research behind it.

His detractors point to the absence of the condition being listed in the book considered by many to be the psychiatrist's Bible: the storied DSM-IV handbook.

'It does not exist'

"Sex addiction is a specious condition -- it does not exist," said David Hersh, a clinical sexologist based in Nelson, B.C.

Addiction is a physiological dependence that must be accompanied by withdrawal symptoms, Hersh said. Unlike alcoholics, who experience various symptoms when they can't get a drink, denying someone sex doesn't create the same result, he said.

Hersh scoffed at the notion of sex addiction, calling it "silly" to use the term for someone who has allowed sex to become a driving force in their life.

"(It) has a moralistic quality to it and a quality of lack of responsibility," he said. "They give up the control to some outside force."

Hersh said he's not surprised by the abundance of therapists promising to save people from sex addiction; as the saying goes, sex sells.

An average private practice in Canada might charge anywhere from $100 to $150 per session, Kalogeropoulos said.

Treatment involves tracing the root of the problem, then setting limits to the behaviour by making gradual changes in the patient's lifestyle, he said.

"You can't just stop this cold turkey -- it's really hard."

Deeper-seated issues may be uncovered in the process, he said, but it's not an excuse to keep the person in therapy longer.

"We don't create these problems," he said, adding there's a one- to three-month waiting list for his clinic. "My goal, when I see people, is to try and get them to progress as quickly as possible so I can move on and help other people."

In 10 years practising sex therapy, Vancouver-based clinical sexologist Pega Ren said she's never encountered a case of sexual addiction -- a term she opposes.

"People who are having lots of great sex with people that they love and feel close to aren't considered sex addicts, and they don't need therapy," Ren said.

Some people who claim to suffer from sexual issues have "lots of sex, little feeling," she said.

"It's poor impulse control layered onto desperately unhappy relationships."