Prince William says he's proud of Princess Diana for revealing bulimia battle

Joined by little brother Prince Harry and wife Kate Middleton, Prince William has taken on the cause of mental health awareness with the charity drive Heads Together. And now, in a bid to shine a light on eating disorders, the royal has has spoken about his late mother Princess Diana's battle with bulimia in a new documentary

For Wasting Away: The Truth About Anorexia, the father-of-two sat down with former TV news presenter Mark Austin and his daughter Maddy, who was diagnosed with anorexia in December 2012 – but has thankfully made a full recovery. After welcoming Mark and Maddy into his Kensington Palace home, the Prince told the pair that there's a need to "normalize the conversation about mental health", adding: "The fact you are speaking out is incredibly brave, but it should become very normal."

Prince William spoke to Mark Austin and his daughter Maddy in the British TV documentary

William's mom Princess Diana first revealed she had suffered from bulimia in Andrew Morton's book Diana: Her True Story in 1992, and spoke about the disorder again in 1995 during her interview with Panorama. In the new documentary, Maddy tells William, "I was really inspired by what your mum did", to which he replies: "We need to be matter-of-fact about it, and not hide it in the dark where it festers."

The Prince said he was proud of his mother for speaking publicly about her battle with bulimia Photo: Getty Images

Mark asks the Prince if he is proud of his mother for sharing her story with the public. "Absolutely," William, 35, replies. "These things are illnesses and they need to be treated. Mental health needs to be taken as seriously as physical health."

He later added: "I really hope [my children] George and Charlotte can grow up in a world where mental health is completely normalized and where we can all talk about it openly and honestly. We can talk about stuff and it is not a weakness and not to be ashamed of."

Wasting Away: The Truth About Anorexia will air on in the UK on Channel 4 this Thursday, August 24.

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