Your comment may seem harmless, but it's really not.

Those quizzes you see popping up on your Facebook Newsfeed may seem like a harmless guilty pleasure, but if you're not careful they could leave you victim of identify theft.

The Sutton Police Department in Massachusetts shared a scary post on their Facebook page last week warning social media users that those fun questionnaires could actually be revealing personal information to scammers.

"Please be aware of some of the posts you comment on," the department wrote in a Facebook photo post that now has more than 200,000 shares. "[These questionable posts] ask what was your first grade teacher, who was your childhood best friend, your first car, the place you [were] born, your favorite place, your first pet, where did you go on your first flight, etc ...Those are the same questions asked when setting up accounts as security questions. You are giving out the answers to your security questions without realizing it."

Here's one example information-prompting post we found searching Facebook: a fun What's Your Elf Name? game that crops up every holiday season. The idea seems harmless enough, delightful to join in on, and you may even want to tag friends to participate. The original poster likely has no harmful intentions, but its posts like this that push you to publicly share specific personal information and your full name is right there with it. One click to your profile, and a stranger could learn where you live as well.

Rachel Rothman, Chief Technologist for the Good Housekeeping Institute, echoes the police warnings.

"A nugget of information in isolation may not seem like a big deal, but combining that with other data that may be out there can result in a greater threat," she says. "Be mindful of photos or posts that could give away information about your location or self (like your birthday) and consider if you are posting something that could be used to locate you offline or make it easier for someone to figure out any of your passwords."

Rothman also recommends using "fake" information when filling out password recovery prompts (like your mother's maiden name or the name of your first teacher) that isn't trackable to you in any way.

But above all, it's important to remember that everything you post on social media is public, no matter how secure your settings are.