Why Does Sex Feel So Good, Anyway?

There's a reason that sex toy shops choose names like Pleasure Chest, Good Vibrations, and Sugar. All of these words invoke the tingling, heart-pumping, all-over 'yum' feelings many people associate with having sex.

There's no question that great, consensual sex feels amazing. But why does it feel so good? What's actually happening inside someone's brain and body to create that euphoria?

According to sexologist Laura McGuire, PhD, there are three main physiological reasons someone feels sexual pleasure: the pudendal nerve, dopamine, and oxytocin.

The pudendal nerve is a large, sensitive nerve that allows someone's genitals to send signals to their brain. In people who have vulvas, it has branches in the clitoris, the anus, and the perineum (the area between the anus and the vulva or the anus and the penis). In people who have penises, the pudendal nerve branches out to the anus, the perineum, and the penis. "It’s important for women to realize that the nerve doesn’t have much concentration inside the vaginal canal," Dr. McGuire says. "Most of the pudendal nerve endings are focused on the clitoris." That's why it's common for people who have vulvas to struggle reaching orgasm from penetrative sex alone, and why the clitoris is often considered the powerhouse of women's sexual pleasure.

The pudendal nerve explains how signals get from someone's genitals to their brain during sex, and then the brain releases dopamine and oxytocin, which causes a flood of happy, pleasurable feelings. "Oxytocin is often called 'the love hormone,'" Dr. McGuire says. "It’s what makes us feel attached to people or things." Oxytocin is released during sex and orgasm, but it's also released when someone gives birth to help them feel attached to their baby, she says. "That’s the big one that makes you feel like your partner is special and you can’t get enough of them."

Like oxytocin, dopamine helps your brain make connections. It connects emotional pleasure to physical pleasure during sex, Dr. McGuire says. "So, that's the hormone that makes you think, that felt good, let’s do it again and again and again," she says.

Oxytocin and dopamine are both in a class of hormones considered part of the brain's reward system, says Lawrence Siegel, a clinical sexologist and certified sexuality educator. As someone's body reaches orgasm, they flood their system because the brain is essentially trying to medicate them, Siegel says. "The brain seems to misunderstand sexual arousal as trauma," he says. As someone gets aroused, their heart rate increases, their body temperature goes up, and their muscles tense, all of which happen when someone's body is in trouble, too.

"As that continues to build and increase, it reaches a point when the brain looks down and says 'Uh,oh you’re in trouble,'" Siegel says. "An orgasm is a massive release of feel-good chemicals that leaves you in a meditative state of consciousness."

Yet, not everyone desires sex. So how do we explain asexuality? Science doesn't have any solid answers, Dr. McGuire says, although it's important to know that asexual people don't choose to be asexual any more than gay people choose to be gay. While we don't know what makes someone asexual, it's pretty certain that there's no physical difference between asexual people and everyone else, Siegel says.

"It’s not correct to say that people who identify as asexual don’t experience pleasure," he says. "They just don’t have the desire to have sex." Desire is ruled by different hormones, most notably testosterone. But even that might not fully explain why someone isn't interested in having sex. "It feels like a different appraisal or reaction to the experience in their body," Siegel says.

While everybody has a pudendal nerve and can experience the release of dopamine and oxytocin that happens with sex, not everyone will experience that release as pleasurable or experience the same level of pleasure. "People are very complicated," Dr. McGuire says.