Last year, researchers at the University of Buffalo in New York released a study on marijuana that gave even the anti-pot crowd pause for thought. They discovered that couples who smoke together are less likely to engage in domestic violence. Though the results hardly came as a surprise to marijuana users, the study asserted that marijuana use was predictive of lower levels of aggression.

What's more, pot is also associated with higher levels of intimacy. And that begs the question (a question that many researchers have attempted to answer over the last 30 years): How does marijuana influence sexual behavior? 

For thousands of years, people have been using marijuana as an aphrodisiac. It was a central component of the ancient Indian Ayurvedic medicine system, which used pot to increase libido; it was part of some Tantric sex rituals, where practitioners would drink a "spiced marijuana milkshake" called bhang; and in modern times, anecdotal evidence suggests that the practice of smoking marijuana and having sex is alive and well.

But when it comes to science of sex and pot, researchers are divided. Interest in establishing the relationship between marijuana consumption and libido has been high, of course, but what scientists have found often seems at odds with the reported experience of users. That is, researchers have found that marijuana doesn't act as an aphrodisiac per se, but it does affect certain sexual organs in a way that boosts sex drive in some.

Back in 1981, the New York Times described a study that came out of the University of Texas, which looked at the sexual activity and biochemistry of mice that were administered varying doses of THC, the main, psychoactive component of marijuana. Published in the journal, Science, the study ostensibly resolved the conflicts between scientific findings (which, up to that point, maintained that the substance had an inhibiting effect on libido) and reported experience (which maintained that sex and pot were complementary).

The researchers measured the amount of testosterone in the subject's bloodstream and determined that THC stimulated testosterone production in a significant way, within minutes of the initial administration. The hormone level spiked, they found, to more than six times the average amount.

"In a person smoking marijuana, the THC enters the bloodstream very rapidly," Dr. Susan Dalterio told the Times. "The drug's almost instant effect on the testes, as shown in the study, would seem to account for the dramatic reports of sexual arousal during and after smoking."

This finding led several other researchers to form their own theories about the sexual effect of marijuana use, including psychologists at the University of Kansas, who surveyed college students in an effort to demonstrate that pot did influence sexual behavior. The students they interviewed reported using marijuana before having sex, and the results of their survey seemed to support the claim that the substance enhanced the experience. 

Though it didn't increase the number of orgasms one had or prompt more sexual initiations between partners, marijuana did appear to have an "aphrodisiac-like" quality, as earlier studies cited. 

"Over two-thirds reported increased sexual pleasure and satisfaction with marijuana," the study's lead author wrote. "Increased desire for a familiar sexual partner was reported by about one-half. The sensations of touch and taste were particularly enhanced by marijuana. Many felt marijuana was an aphrodisiac."

In a more recent survey, a Psychology Today blogger asked readers to report their own experiences with marijuana and sex. Sixty-seven percent of respondents said that pot enhances sex, but another subset of readers—12 percent—claimed that "marijuana destroys sex." Then you have the more scientifically minded respondents, who reasoned simply that it depends. Twenty percent, in this case, said that the sexual effect of marijuana varies depending upon the dose, strain, and mood of the smoker.

In an interview with High Times, the de facto counterculture magazine, Dr. Lester Grinspoon said that while marijuana is not an aphrodisiac in the scientific sense of the word, it does seem to enhance sex. Contrary to what subscribers of the ancient Indian Ayurvedic medicine system believed, cannabis consumption is not associated with long-lasting erections, the psychiatrist explained; however, he does not deny the anecdotal evidence either.

"There's no doubt that when people are high, they're more sensitive to their sexual feelings and urges," Grinspoon said. "Look, if you come to me and tell me that you're having difficulty in getting turned on sexually, or that you're experiencing premature ejaculation or erectile dysfunction, I might ask, 'Have you ever tried marijuana before? It won't hurt you. You might try it.'"