Singer Demi Lovato has been a huge advocate for those suffering with mental illness since she began opening up about her own struggles with bipolar disorder, substance addiction, and eating disorders.

And now the "Sorry Not Sorry" pop star is using her voice once again for those who also live with mental illness.

Lovato recently announced on "Good Morning America" that she is bringing CAST Centers on tour with her to provide free group wellness sessions for her fans. Lovato knows firsthand that CAST works -- it's the treatment and wellness program she personally attended.

Concert attendees will have the chance to sign up for the intimate chats online, which will be offered to those 16 years and above with a ticket purchase. The sessions will be led by CAST founder and CEO Mike Bayer, and will feature special guest speakers talking about their own personal journeys with mental health and wellness.

"It's important that I use my voice for more than just singing, and I just know how important it is to use my platform to help others and to share my story in hopes it inspires people to either get into recovery or better themselves. Whatever it is, I just want people to know they're not alone and I'm here for them," she told GMA host Robin Roberts. "I think it's very important to take away the stigma of mental illness. I actually have bipolar disorder, and I'm very open about that because I think that mental health affects so many people and we need to take the stigma away from it."

This isn't the first time Lovato has offered CAST sessions for her fans. She also offered them during her "Future Now" tour in 2016, which featured speakers Joe Jonas, Nick Jonas, Phil McIntyre, Bea Miller and Metta World Peace, among others.

"I want to do this because one, it was such an incredible experience the last time we did this on tour," Lovato told Roberts. "I've actually met people that go to CAST because they went to CAST on Tours and realized they needed to get sober or they needed to better themselves in some other way and it’s changed lives and I want to be able to do that again. It's a part of my whole … life, about giving back and I think it's really important that I continue to do this while I'm on tour."

Additionally, through CAST, Lovato will be partnering up with one mental health and/or wellness charity in each city, encouraging fans to donate via text message during the show itself.

Using celebrity for a good cause is always a good thing, and Lovato giving a voice to an often voice-less health issue, like mental illness, which affects so many people, is commendable. As the singer once said, "If I'm able to use my voice to do good in the world then I definitely want to do that."

For more info and to sign up, check out castontour.com.

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