Transcript for Jennifer Aniston Opens Up About Being Dyslexic

Jennifer aniston revealing a secret struggle she's battled for years. Telling "The Hollywood reporter" she was diagnosed with dyslexia in her early 20s. ABC's Abbie Boudreau has her story. Reporter: She's Hollywood's favorite "Friend." Jennifer aniston. Starring in the emotionally gripping new movie "Cake." I am in a lot of pain. Reporter: But it's her real-life struggle with dyslexia that the 45-year-old actress is now opening up about for the first time. She grew up thinking she was stupid and that's a horrible way to spend your upbringing. Reporter: Looking flawless on the February cover of "The Hollywood reporter" the recent golden globes nominee went years wondering what was wrong with her telling the magazine "I thought I wasn't smart." I just couldn't retain anything. Then she says in her early 20s she went to the doctor for prescription glasses E. Explaining my eyes would jump four words and go back two words. That's when doctors told her she had dyslexia. Jennifer says I felt like all of my childhood trauma-dies, tragedy, dramas were explained. Dyslexia is a learning disorder where people have difficulty Reading and struggle converting words into sounds, experts say it can often go undiagnosed until adulthood. But Jen's not the only Hollywood heavyweight with dyslexia. Even her fiancee Justin thoreau says he's dyslexic along with Channing Tatum, Orlando bloom and whoopi Goldberg who opened up about it on "Gma" in 2013. I learned to read late because I'm dyslexic and Reading was tough. Once I learned to read I just sort of drank it up. Reporter: Despite it being tough the "Horrible bosses" star didn't let it hold her back. Yet it hasn't prevented her from making an extraordinary life for herself. Reporter: For "Good morning America," Abbie Boudreau, ABC news, Los Angeles. And ABC news chief health and medical editor Dr. Richard Besser joins us with more on this. Good to see you, rich. Jen diagnosed in her 20s. Not uncommon, is it? Unfortunately, it's not but every time you hear one of these stories, it's really a tragedy because when a child doesn't learn that they're having -- that they have a learning difference, it can lead to problems with self-esteem. They can think they're not smart but there's absolutely no connection between intelligence and dyslexia but that's not how children feel when they're not able to learn in the same way as other kids. Especially difficult for Ang actress that has to read and memorize descriptions. Children develop coping mechanisms so oftentimes you'll see they're able to take in information that they hear and memorize it and spit it back but as you were saying whoopi Goldberg, terrific actress has dyslexia. Tom cruise suffers from dyslexia. There are people in every single field who have dyslexia and they've learned ways around that, so that it doesn't hole them back. Channing Tatum, as well has it. He deals with it. A lot of people think of the switching of letters or reversing Numbers but there are a lot more sips a parent should look for. There are. As a pediatrician I'm always looking for learning disabilities because it can have such an impact on a child's life if you pick it up early but it is more than reversing letters so in preschool children what you'll see, a child can't learn nursery rips. They have trouble with rhyming. It's not letter reversal but how your brain processes information you're taking in for Reading and for some reason rhyming is one of those things and then the next thing you'll see is trouble learning letters and Reading out loud so much more than that. There's help out there for adults, diagnosed later. Exactly. Don't put it off and say it's too late. You can learn coping mechanic niches. Way to learn better for you and understand why you didn't like school when other kids did and that could be very, very helpful. Very helpful information. I'm glad she came out. I'm glad you're here to. We turn to "The morning

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