Transcript for Is social media causing depression in teens?

We turn to our cover story taking a closer look at the risks of social media and how necessary perfect-looking pictures could fuel or hide anxiety and depression in young adults and Paula Faris with the story of one teen who seemed to have it all but was fighting a secret battle. Reporter: Maddie was the all-American girl. A college athlete with brains and beauty. Her Instagram feed is the perfectcollege experience feed and then if you even go back, it's the perfect summer before college. Reporter: But what her social media did not show was her intense battle with depression that ultimately led to her death by suicide at just 19 years old. If you look through her Instagram account, there are really no red flags as to her struggles. It's hard to consume her Instagram feed because you do know the end of her specific story and they don't add up. Reporter: In a new book "What made Maddy run" ESPN columnist Kate Fagan explores her life whose battle with depression she believes was worsened by social media. So many youth right now are presenting perfection when in reality there's a much different picture going on. Madison knew that her Instagram feed was a false reflection but he couldn't see that her peers were also reflecting something that maybe wasn't totally real. Reporter: Experts say while many students are posting highlight reels of the perfect college experience, they're also hiding their struggles, anxiety and depression. Researchers at Stanford university call this the duck syndrome. Referring to the way a duck appears to glide effortlessly across the water. While underwater its feet work frantically to stay afloat. It's really about maintaining a healthy perspective working hart but also recognizing that you don't have to be perfect to be happy. Reporter: With more college students diagnosed with depression and 75% of mental health conditions beginning before the age of 24, college has become such a critical time for today's youth. There's so much pressure to be at all of the parties, to look like you're having the best time of your life. Reporter: Larissa may said she felt it as a student at Vanderbilt. My sophomore year I struggled with anxiety and depression and social media was definitely a trigger for that because I was always looking at everyone else's and, you know, trying to understand why were they so happy and why was I not? Reporter: But in her senior year she fought back creating half the story. A school project that turned into a movement encouraging college students to realize the truth behind filtered photos and perfect posts. For "Good morning America," Paula Faris, ABC news, New York. What a great idea. Psychiatrist Dr. Gail Saltz is here with us and you're so happy we're talking about this. I am so happy we are. How does it play a role? Multiple studies show those that spend a huge amount of time on social media, in fact, do have higher rates of depression and anxiety. On the flip side, things like this are starting to happen where people are starting to talk about mental health issues on social media and that may make an impact. I saw Instagram is doing that in particular and knowing that it is a discussion that needs to be had and tell people how it can show up differently in teens and young adults, depression. Absolutely. Teens and young adults might look happy some of the time so on their social media stuff or even when you're seeing them and it may mask what is this underlying depression whereas adults tend to look sad all the time but if you see a change in function in your teen or young adult like they were doing well in classes and now not so much. If you see a loss of pleasure in doing things, they don't really want to go to the party, they don't really want to engage with friends and part of the loss of function might be they're not going to the meals, they're not going to their classes, if you see any expressions of hopelessness and this is a really important thing, because they might post something that seems like, oh, they're just being dramatic or something, take it seriously. If you're a parent, if you're a friend, somebody at the school and you see a post that says, you know, something like what's the point? Or, you know, what am I doing here? Take it seriously. Is it more that parents and others can do to help. Absolutely. You absolutely should align expectations. Kids go off to college thinking it's going to be the biggest, best time of their life and everybody reinforces that, you know what, that's not true. They're going to be ups and there are going to be downs and you need to let them know that so that when it happens, they're not like what's going on? Something is terribly wrong with me and give them social media expectations so, hey, tell them, being on all the time can lead to depression. Have real relationship, not just social media relationships. You really want to check in with them. You want to check their mental health temperature periodically as the parent. So not like tell me everything great going on. Tell me what's really going on. Real conversations. And check with them about mental health options around. Needs to be discussed. Ga, thank you as always.

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