People have taken breaks from Facebook, the biggest social network on the planet, in an effort to improve their mental health and due to concerns about their privacy. Now, there’s another reason young people in particular might want to take a break.

Students whose grades are below average could boost their results if they devoted less time to Facebook and other social-networking sites, according to research published this week. The study, led by James Wakefield, a senior lecturer at the University of Technology Sydney, examined the time first-year university students spent on Facebook FB, +2.12% and how it impacted their grades.

Such students are likely already struggling with their ability to focus. “Time spent on social networking platforms puts lower academic achievers at higher risk of failing their course,” Wakefield said. “We found that if they used Facebook for three hours a day — not substantially higher than the average of just under two hours — the difference was around six marks in a 60-mark exam or 10%.”

The research, published in the latest edition of Computers & Education, a peer-reviewed journal, with co-author Jessica Frawley, a lecturer at the University of Sydney, looked at university students studying STEM — science, technology, engineering and mathematics — and business. (Facebook did not return a request for comment on the study.)

More than 500 students enrolled in a first-year class, “Introductory Accounting,” at an Australian university took part in the study; they had an average age of 19. The researchers controlled for other factors that might influence their achievement, including whether they were planning to major in accounting, as well as their age and gender.

Facebook CEO Mark Zuckerberg faced a grilling on Capitol Hill last month by members of the House Financial Services Committee over his proposed cryptocurrency project, Libra, and the platform’s role in the 2016 U.S. presidential elections. The #DeleteFacebook hashtag trended on Twitter TWTR, +1.62% in the wake of that controversy.

Many consumers vowed to deactivate their accounts in 2018 after revelations that U.K.-based campaign strategy firm Cambridge Analytica had used millions of Facebook users’ personal data without their permission. Some 44% of users between the ages of 18 and 29 deleted the Facebook app from their phone in the wake of the scandal, according to a survey by Pew Research Center.

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In the aftermath of that scandal, all Facebook users received a message on Facebook called “Protecting Your Information,” laying out which third-party apps had access to their individual Facebook profiles. (Zuckerberg also issued a mea culpa and pledged to be more careful when vetting third party apps, but said fixing the problem could take years.)

Last month, #DeleteFacebook trended once more after a report from Politico that Zuckerberg held private meetings with conservative journalists and commentators over the summer. Despite these recent controversies, Facebook reported an 1.6% increase in active users in the third quarter from the previous year, bringing the global total to 2.45 billion monthly active users.

Of course, social media also connects people. Facebook, Instagram, Snapchat SNAP, +1.52% and Twitter make it easier to maintain relationships, access health information, improve mental health and even avoid serious psychological distress, according to a separate study released earlier this year by Keith Hampton, professor of media and information at Michigan State University.

“Taking a snapshot of the anxiety felt by young people today and concluding that a whole generation is at risk because of social media ignores more noteworthy social changes, such as the lingering effects of the Great Recession, the rise in single-child families, older and more protective parents, more kids going to college and rising student debt,” he said.

Not everyone agrees with this analysis. A separate recent study conducted by psychologists at the University of Pennsylvania showed quite the opposite: a link between time spent on social media and depression and loneliness. Those who drastically cut back their use of sites like Facebook, Instagram and Snapchat felt significantly better about their circumstances.

“It was striking,” said Melissa Hunt, a psychology professor at the University of Pennsylvania who led the study. Over the course of three weeks, the rates of depression and loneliness fell significantly for people who limited their social media use. Many of those who began the study with moderate clinical depression finished just a few weeks later with very mild symptoms, she added.

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