Editor's Note: (This article contains a candid discussion about pornography and other adult themes. For more on online pornography, watch "This Is Life with Lisa Ling" on CNNgo. Catch new episodes Sundays at 10 p.m. ET/PT.)
(CNN) At a certain age, every kid learns about the difference between fantasy and reality, whether it applies to fairy tales, video games or superhero movies.
But when do they learn about the difference between real sex and porn?
For the generations who've never lived without Wi-Fi, the internet is often the first place they're exposed to sexual imagery. And in the absence of good, comprehensive sex education, some kids may think it's the only way to actually learn about sex.
"The sad fact is that more than half of our children get their first 'sexual education' from adult films on the internet," said Dr. Mark Schoen, founder of SexSmartFilms.com and former director of sex education at the Sinclair Intimacy Institute. What's missing is a sense of context and conversation around this imagery -- a conversation that would help a young person distinguish between real sex and porn sex.
Although many sex educators are advocating for this kind of porn literacy in schools, the conversation also needs to happen at home.
In general, there can be real benefits from having frank discussions about sex, said Debby Herbenick. In one recent study by Herbenick and her colleagues at the Indiana University School of Public Health, exposure to porn was only associated with an increased probability in having unprotected sex when parents had little-to-no sexual health communication with their children. When parent-teen sexual health communication was high, pornography use was unrelated to teenagers' engagement in unsafe sex.
Here's how to approach "the talk" in the age of online porn.
"Parents would be wise to start discussing sexually explicit media during childhood," said Herbenick. "It's not just porn that they need literacy about — it's Hollywood movies, music and social media, too."
Rather than viewing access to porn as a negative, welcome it as an opportunity to educate your kids. "In my experience, the more sex ed a child receives from their parents, the less likely they are to develop shame around sex and use pornography in a compulsive or unhealthy manner," said sex therapist Kimberly Resnick Anderson.
"Starting the conversation can be as easy as saying something like, 'I know this might seem like it's coming out of nowhere, but I'm concerned about the messages you are getting about sex, sexual behaviors and what's real or normal from the stuff that's out there,'" said sexologist Lanae St. John.
Or you might do some advance planning. "A conversation on sex and porn should allow for honesty and the time it takes to have a serious discussion," advised sex therapist Heidi Crockett. "I recommend arranging an agreed upon time so that both parent and child can bring their questions and thoughts to the table."
Remind your child that porn is meant for entertainment, not education, in terms they can understand.
"I tell them that just as the 'Fast & Furious' movies are not driver's ed, porn is not sex ed," said St. John. Explain that just like movies, porn portrays how we might fantasize about things but not act on them.
Likewise, you can stress that masturbation -- to porn or otherwise -- and sex are two different experiences. "It's fun to text our friends or play video games with them online, but it's another thing to hang out in person," said sex therapist Kristen Lilla. "Porn can also be fun to watch, but it doesn't mimic or replace real-life sex and relationships."
Part of what makes porn tough to talk about is how divisive it's become. You might hear from some adults that porn use has led to dependency, erectile dysfunction, fear of intimacy and other problems. For others, it's simply part of a healthy sex life.
The truth is that medical experts don't know for certain whether porn use is truly responsible for all of the effects attributed to it; so far, there isn't a clear scientific consensus around the influence of porn on the human adult brain, much less the teenage brain.
While some experts say that porn is highly addictive, others say that the concept of true porn addiction isn't supported by scientific evidence. Impulsive or compulsive porn use, this camp says, is usually a symptom of something else, such as depression or anxiety.
The only thing we do know for certain is that the more open parents are with their kids about sexual health, the better.
View your conversations as laying the foundation for helping children question all the media they consume.
"We begin this process of becoming aware of how roles or stereotypes are portrayed when you watch TV or PG movies with your kids beginning when they're 7 to 8 years old," said sex therapist Sari Cooper. "Bringing up some of the uncomfortable feelings one has when watching a film with younger ages because of the way a woman, person of color, or a person with disability was portrayed begins a training of critical thinking with your children."
However you choose to approach it, know that "the talk" is really a series of conversations. When you discuss topics like sexuality, masturbation and porn early on, you open the door for trust and honesty with your kids — and that helps build a foundation for good sexual health throughout their lives.