LOS ANGELES – Does a predilection for porn mean bad news in bed? That’s the conclusion of many clinicians and the upshot of anecdotal reports claiming a man’s habit of viewing sex films can lead to problems getting or sustaining an erection.

But a new study from UCLA and Concordia University — the first to actually test the relationship between how much erotica men watch and erectile function — indicates viewing porn is unlikely to cause erectile problems and may even help sexual arousal.

The study, published in the online journal Sexual Medicine, was conducted by Nicole Prause, an associate research scientist in the Department of Psychiatry at the UCLA Semel Institute for Neuroscience and Human Behavior, and Jim Pfaus, a professor in Concordia’s Department of Psychology and Center for Studies in Behavioral Neurobiology.

Prause and Pfaus analyzed data collected from 280 male volunteers during previous studies in Prause’s lab, specifically focusing on the effect watching erotica had on subjects’ sexual arousal.

All the men reported the average number of hours per week they viewed sex films — which ranged from zero to 25 hours — and also completed a questionnaire that measured levels of sexual desire.

Of the 280 volunteers, 127 of them had regular partners and completed the International Index of Erectile Function, a questionnaire that requires men to rate their experience with erectile function.

While in the lab, participants also viewed films showing a man and woman having consensual vaginal intercourse, and then reported their level of sexual arousal.

“When we analyzed the data from these prior studies, we found that the men who had watched more sex films at home were more aroused when they watched sex films in the lab,” Prause said. “While one could object that this was expected since they like sex films, the result is important because clinicians often claim that men get desensitized by watching these films.

“They are responding more strongly to very vanilla erotica than the guys for whom the films are more novel,” she continued. “While this association doesn’t establish a cause, it proves viewing erotica at home is not desensitizing and perhaps even sensitized the men to respond more strongly.”

Prause and Pfaus also found no relationship between viewing sex films and the incidence of erectile dysfunction in men who are sexually active.

“Many clinicians claim that watching erotica makes men unable to respond sexually to ‘normal’ sexual situations with a partner,” Prause said. “That was not the case in our sample.”

In fact, according to Concordia’s Pfaus, the study’s data indicates erectile dysfunction may be wholly unrelated to porn-watching.

“While many people think easy access to porn leads to problems in the bedroom, our study suggests the opposite: that erectile dysfunction is most likely caused by the same issues that have been known for some time, such as performance anxiety, poor cardiovascular health or side-effects from substance abuse,” he said.

Prause agreed, saying blaming erectile dysfunction on porn actually may harm patients.

“We have strong psychotherapy and medical interventions to help with erectile problems,” she noted. “These data suggest that inventing a new problem — porn causing erectile problems — for which there is no tested treatment, may be a disservice to patients,” she said.

A larger issue concerns recent assertions that watching porn causes addiction and ruins relationships. Pfaus said the study’s data disputes those claims.

“The study participants represent a good cross-section of men that view porn on a regular basis,” he said. “The fact that doing so increased their arousal to the erotic stimuli should cause clinicians and sex therapists to rethink their attributions.”