The 23-year-old opened up about the pressure she feels to be starring as the lead in the upcoming superhero blockbuster X-Men: Dark Phoenix, describing herself as a "nervous wreck".
Turner stated she has suffered from depression and anxiety in the past, and continues to experience mental health issues.
"Definitely. Depression for sure, anxiety, all those things," the actor tells Rolling Stone magazine.
"I still experience it, but I had therapy, I'm on medication, and I feel so much better. The fact that I spoke to someone changed my life."
Turner has spoken openly about her views concerning mental health on several occasions in the past.
In January, the actor replied to a tweet posted by Piers Morgan in which the Good Morning Britain co-host said that he agreed with the view that celebrities are trying to make mental health problems "fashionable".
"Or maybe they have a platform to speak out about it and help get rid of the stigma of mental illness which affects one in four people in UK per year," Turner wrote in response.
"But please go ahead and shun them back into silence," she added.
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The X-Men: Apocalypse star then shared a thread on Twitter shedding more light on the topic, saying that people who joke about mental illness "can't comprehend what it is like to have or know someone with an illness like this".
In Glamour magazine's spring/summer 2019 issue, Turner's Game of Thrones co-star and close friend Maisie Williams explained that Turner is a strong advocate of therapy.
"I can’t tell you the amount of times Sophie said, 'Go to therapy,' before I actually did," Williams.
"She really helped me through some messy break-ups and some friend break-ups."
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However, Turner believes therapy is more widely accepted among younger people.
“It’s definitely a generational thing,” she says.
“My mum still asks me, ‘Why do you need a therapist?’"
If you're experiencing a mental health problem or supporting someone else, you can call SANEline on 0300 304 7000 (4.30pm–10.30pm every day).
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