Imagine what would happen if your school’s health class was taught by a cigarette salesman. Chances are, you wouldn’t hear much about lung cancer or how much shorter the typical smoker’s lifespan is. He might even try to tell you that smoking could boost your sprint time. Sounds ridiculous, right? But that’s the kind of education millions of teens are getting about sex every day.

While porn is often called “adult material,” many of its viewers are well under the legal age. [1] In fact, the majority of teens are getting at least some of their sex ed from porn, whether they mean to or not. [2] And just like cigarette commercials show healthy people puffing away instead of the cancer-causing reality, porn is offering a completely warped idea of what partners, sex, and relationships are really like. [3]

Studies show that people who consume porn are far more likely to believe that things like group sex or dangerous sex acts are more common than their non-porn-consuming peers. [4] Why? Because that’s what they’ve seen in porn. In one study of popular porn videos, the average number of sexual partners in a scene was three, although the number ranged as high as 19. Today’s mainstream porn sites include whole categories of unprotected sex with strangers, brutal gang rape, and other dangerous and violent sex acts.

And porn keeps getting worse.

“A competitive market means that pornographers are trying to outdo each other to come up with the most extreme images,” explains Dr. John Wood, a therapist who works with youth addicted to pornography. “This contest to push the boundaries means that straight intercourse is considered too boring. Images of brutal anal sex and women being humiliated and degraded by two or more men at any one time are the new norms.” [5]

Researchers are finding that porn’s influence can and does find its way into teenager’s sexual behaviors. [6] For example, people who have consumed a significant amount of porn are more likely to start having sex sooner and with more partners, to engage in riskier kinds of sex that put them at greater risk of getting sexually transmitted infections, and to have actually contracted an STI. [7]

Sociologist Dr. Michael Kimmel has found that men’s sexual fantasies have become heavily influenced by porn, [8] which gets awfully tricky when their partners don’t want to act out the degrading or dangerous acts porn shows. [9] As a result, individuals who consume pornography have been shown to be more likely to go to prostitutes, [10] often looking for a chance to live out what they’ve seen in porn. [11] In one survey of former prostitutes, 80% said that customers had shown them images of porn to illustrate what they wanted to do. [12]

But just as harmful as the things porn shows is what it doesn’t show. Pornography doesn’t give an accurate picture of what healthy sex is like; they cut out things like talking, cuddling, bonding touch, and other ways partners are responsive to each other’s needs and preferences. [13] They also cut out the consequences of the kinds of sex portrayed in porn. [14] No one ever contracts sexually transmitted infections in porn. There are no unplanned pregnancies, no cervical cancer, no intestinal parasites, and no skin tearing or bruises.

In porn, no matter how rough a person treats their partner, nearly everything looks like it feels good. [15] In fact, in the study of popular porn videos, in nine scenes out of 10, a woman was being hit, beaten, yelled at, or otherwise harmed, and the result was almost always the same: the victim either responded with pleasure or had no response at all. [16]

Not only does porn offer a warped version of sex education, it also delivers that education in a way perfectly tailored to how our brains learn. [17] (See How Porn Changes the Brain.) Images are especially powerful teachers since they can pack in a whole lot of information that the viewer can understand very quickly. And while words are often interpreted as mere opinions, our brains are more likely to accept images as facts. After all, it’s a lot more difficult to argue with something you’re seeing happen in front of you. [18]

And what messages are young people learning so effectively from porn? A recent study of adolescent porn use concluded that the major messages presented by porn are male domination, hypermasculinity, and making male sexual pleasure the top priority. [19]

What kind of education is that?

“It’s sad,” says Dr. Gary Brooks, a psychology professor who studies the effects of porn. “Boys who are initiated in [to] sex through these images become indoctrinated in a way that can potentially stay with them for the rest of their lives.” [20] And think about it, what messages does that send to young women and girls who are consuming this content as well?

That’s what porn is: indoctrination, the process of teaching a person or group to accept a set of beliefs uncritically. It isn’t just entertainment. It isn’t just titillating. It teaches a detrimental message from a specific worldview. We can limit the advancement of porn’s ideals by spreading the truth, especially to young people. And for those who feel caught up in porn’s web, it’s never too late to stop and even turn back its harmful effects. Click here to find out how.