Mental health conditions are often treated as a taboo thing as the sufferers are trying to hide their condition. However, several celebrities revealed their mental health issues to give awareness and help a lot of people, who have the same problem, to seek for help.

According to Bored Panda, one out five Americans are diagnose with mental illnesses. Conditions often vary from depression, anxiety, bipolar disorder, ADHD and eating disorders.

A Plus reported that these A-listers opened up about their disorders, so other people can know what they've been true and proved that they are not alone.

Ellen DeGeneres -- Depression

A photo posted by Ellen (@theellenshow) on Oct 23, 2015 at 3:17pm PDT

“I lost my show. I’ve been attacked by hell. When I walked out of that studio after five years of working so hard, knowing that I had been treated disrespectfully for no reason other than I was gay, I just went into this deep, deep depression.”  

Adam Levine -- Attention Deficit Hyperactivity Disorder [ADHD]

A photo posted by Adam LevineⓂ️ (@adamlevine79) on Aug 16, 2015 at 3:11pm PDT

"I think now, people notice my ADHD as an adult on a daily basis. When I can’t pay attention, I really can’t pay attention."

Lena Dunham -- Obsessive-Compulsive Disorder [OCD]

A photo posted by Lena Dunham (@lenadunham) on Oct 29, 2015 at 10:24pm PDT

She's been outspoken about her condition and shared her experiences growing up with OCD and what's like to undergo therapy in an article she wrote in The New Yorker in 2014.  

Leonardo DiCaprio -- Obsessive Compulsive Disorder [OCD]

A photo posted by Leonardo DiCaprio (@leonardodicaprio) on Jul 17, 2015 at 10:07am PDT

"I remember my makeup artist and assistant walking me to the set [of 'The Aviator'] and going, ‘Oh God, we’re going to need 10 minutes to get him there because he has to walk back and step on that thing, touch the door and walk in and out again."

John Green -- Depression, Anxiety, Obsessive Compulsive Disorder [OCD]

A photo posted by John Green (@johngreenwritesbooks) on Oct 9, 2015 at 5:39pm PDT

"Like millions of others, I take medication to help treat my mental illness. Treating chronic medical conditions must not be stigmatized."  

J.K. Rowling -- Depression

A photo posted by J.K.Rowling (@_jk.rowling) on Oct 21, 2014 at 7:20am PDT

“I have never been remotely ashamed of having been depressed. Never. I went through a really rough time and I am quite proud that I got out of that.”

Demi Lovato -- Bipolar II Disorder

A photo posted by Demi Lovato (@ddlovato) on Oct 23, 2015 at 4:09pm PDT

“I could either not talk about my stint in rehab and hope that it went away, or I could talk about it and inspire people to get help for their issues as well, so that’s exactly what I did."  

David Beckham -- Obsessive Compulsive Disorder [OCD]

A photo posted by David Beckham (@davidbeckham) on Sep 28, 2015 at 10:52pm PDT

"I’ll go into a hotel room. Before I can relax I have to move all the leaflets and all the books and put them in a drawer. Everything has to be perfect."

Elton John -- Bulimia

A photo posted by Elton John (@eltonjohn) on Nov 2, 2015 at 3:00pm PST

"As soon as I said ['I need help'], I knew that I was going to get better, and I was determined to get better. But it was just a relief to be able to say those."  

Brad Pitt -- Depression

A photo posted by Brad Pitt ️️ (@bradpittoficial) on Oct 25, 2015 at 6:48pm PDT

“This semester I was majoring in depression. I was doing the same thing every night and numbing myself to sleep, the same routine. Couldn’t wait to go home and hide out.”

Jim Carrey -- Depression

A photo posted by Jim Carrey (@officialcarrey) on Nov 3, 2013 at 7:11pm PST

“I was on Prozac for a long time. I had to get off at a certain point because I realized that, you know, everything’s just okay.”  

Angelina Jolie -- Depression

A photo posted by Angelina Jolie (@angelinajolieofficial) on Nov 4, 2015 at 11:13am PST

“I felt I was going into a very dark place, and I wasn’t capable of getting up in the morning, so I signed up for something that would force me to be active.”

Catherine Zeta-Jones -- Bipolar II Disorder

A photo posted by Catherine Zeta-Jones (@catherinezetajones) on Oct 15, 2015 at 1:35pm PDT

“I have a British stiff-upper-lip mentality... When it did come to light, I know I’m not the only person who suffers with it or has to deal with it on a day-to-day basis. So, if I’ve helped anybody by discussing bipolar or depression, that’s great."  

Carrie Fisher -- Bipolar I Disorder

A photo posted by Jorge I. Rivas Jr (@jir.jr) on Nov 4, 2015 at 6:33pm PST

"When my mania is going strong, it’s sort of a clear path. You know, I’m flying high up onto the mountain, but it starts going too fast. I stop being able to connect. My sentences don’t make sense. I’m not tracking anymore and I can’t sleep and I’m not reliable."

Gwyneth Paltrow -- Post Partum Depression

A photo posted by Gwyneth Paltrow (@gwynethpaltrow) on Oct 4, 2015 at 1:25pm PDT

“It was terrible. I thought it just meant I was a terrible mother and a terrible person.”

Watch the science of depression below: