Zachary Levi has a candid message for his younger self.

The Chuck actor, who has been outspoken about his mental health journey, recently shared the piece of advice he would give himself in the past.

"Love yourself, also stop trying to be cool," Zachary exclusively told E! News at the March 14 premiere of Shazam! Fury of the Gods. "You don't need to go hang out with the cool kids. They don't even know who they are."

Adding that "all that stuff is all completely artificial," the 42-year-old further reflected on popularity.

"Nobody cares once you graduate from high school, unless you go to a university that cares and then nobody cares after university," he said. "It's all this weird, bad click system that hurts everybody in it."

Previously, the Tangled actor has detailed his battles with anxiety and depression, revealing last June that he underwent a three week, life-saving treatment at a psych ward. In his memoir, Radical Love: Learning to Accept Yourself and Others, Zachary gave further insight into his healing journey—a move that he hoped would help others.

"Having the privilege to be able to go and see the various therapists and understand the things that I've been able to understand, a lot of people don't get that. They don't have those resources," he shared. "They don't have that time. I wanted to be able to distill as much as I learned and put it down."

He added, "I've been so grateful that the people will send me messages on social media, or I'll meet them in person and the book resonated with them on a very deep level and helped them. And so I'm like, 'OK, mission accomplished.'"

But of course, the journey "doesn't just end where I'm healed," Zachary said. As for what advice he would give others, he emphasized a message of self-love and self-acceptance.

"Reminding yourself every day that you're exactly what you're meant to be," he continued. "You are a product of your environment just as everyone else. Accept yourself radically, forgive yourself radically, love yourself radically."

Shazam! Fury of the Gods is out in theaters on March 17.

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