Nev Schulman offers tips for avoiding "Catfishes"

With an estimated 83 million fake profiles on Facebook, do we ever know who we can trust or who we're talking to online?

Nev Schulman learned this first hand when Megan, the young woman he thought he was romancing on the Internet, turned out to be a middle-aged woman named Angela who deceived him by creating at least 14 fake Facebook profiles.

He shared his story in the 2010 movie, "Catfish." It sparked an MTV show of the same name, where Schulman affirms and debunks America's online romances.

His new book, "In Real Life: Love, Lies and Identity in the Digital Age," explains how people can protect themselves online, and offers helpful signs for spotting a catfish.

"Everybody always says, 'How do people fall for this,' and I say, 'Well I did.' And I was living in New York, and was fortunate to be educated and street smart," Schulman told CBS News. "The truth is, when you're looking for something, whether it's self esteem or affection, people are willing to ignore a lot of red flags and sort of go along with the story because they're getting what they want."

In "In Real Life," Schulman says catfishing is often caused by insecurity about appearance, shame about sexuality or fear of rejection.

"A lot of the time it's because they themselves are insecure or unhappy, so they're trying to create a version of themselves to escape, to perhaps not deal with, or try not to deal with, some of the issues they have," Schulman says. "It doesn't intentionally begin as a lie but it sort of turns into one."

Luckily, Schulman offers a few tips for spotting a catfish. He tells readers to search Google images, examine their interest's photos, contact their Facebook friends and use video verification.

"It's awkward, and that's why people avoid it, but search someone if you're talking to them and you have feelings and it's intimate," Schulman says.

One red flag, he says, is if your partner only posts pictures of themselves.

"It seems silly but we get so wrapped up in these relationships, we don't realize what someone from the outside might say; 'This is ridiculous, how does someone have 200 pictures of themselves and no friends?" Schulman said.

Another key piece of advice: ask your partner to post a specific, non-fakeable photo.

"If someone is using someone else's photos, they've downloaded and stored a lot of them and they'll release them to you slowly," Schulman said. "But if you say, 'Hey can you send me a photo of you holding something very specific,' it's unlikely that they'll have access to that a photo of that person holding that specific item."