Concerned that your teen’s online obsession is doing more harm than good?

Well, you might want to think twice before confiscating their smartphones.

New research finds that there’s a Goldilocks sweet spot when it comes to screen time for teens’ optimal mental well-being.

On the other hand, those who go overboard — or avoid social media altogether — are more likely to experience negative health outcomes, according to sociologists at Dublin’s Trinity College.

“The reality is that digital engagement and social media are a natural part, these days, of young people’s lives and experiences,” co-author and Trinity sociology professor Richard Layte told The Post of his findings.

The longitudinal study, published in the journal “Computers in Human Behaviour,” observed the online habits of 8,568 young Irish people over nearly a decade. The researchers examined how time spent surfing the web correlated with mental health issues such as anxiety, depression and isolation when the participants were ages 9, 13 and 17 to 18 years old.

Turns out the kids who were most well-adjusted (i.e., the least likely to have “adverse psychiatric symptoms”) at ages 17 to 18 spent one to two hours online on weekdays — and two to three hours on weekends.

“This goes against a narrative out there that social media is a negative thing in young peoples’ lives. It follows a path we see with all new technology. When the telephone was first invented, that was seen to be the end of civilization. TV [at its origin] experienced a very similar thing,” Layte told The Post.

“The reality is, [social media] can be a very beneficial conduit through which to have social participation, social contact. But, like many things, you have to do that in moderation. Too little can be damaging, but too much definitely seems to carry risks.”

To the surprise of few, many teens fall into the proverbial “the porridge is too hot” crowd. A 2015 study by Common Sense Media found that kids ages 13 to 18 on average spent nine hours indulging in entertainment media per day.

Kids continuously glued to their tablets may already be “experiencing quite high levels of alienation and loneliness,” Layte said, referring to his findings. Such kids may find themselves in a catch-22, spending “very high levels of time online … to make up for or try to work out what their peers are thinking of them,” he said.

“You can kind of end up here with an exacerbation of existing, underlying mental health concerns or problems.”

But teens who avoid the online world — shunning social media, for instance — could experience negative effects too.

“If you’re not online, on these platforms, interacting with people there, then you’re losing a large part of your network connection. And if you do that, chances are you’re going to miss out on certain opportunities,” Layte said.

He noted that “low time online among girls is particularly associated with peer problems.”

Layte said that the group of teens in his study were particularly interesting to observe, given the rapidly shifting social media landscape they experienced since the research began more than a decade ago.

“We’ve been following these people since [age] 9. If you think about it, age 9 for them was 2008 [when smartphones first boomed], so they were really on the cusp of ‘in your hand social media,’” he said.