Bruce Willis' wife reveals the 'sad truth' about his heartbreaking dementia diagnosis

Emma Heming Willis has shared "the sad truth" about Bruce Willis' dementia battle.

The 44-year-old took to Instagram to share a heartbreaking update with fans as she admitted "there is no cure" to help her husband fight the degenerative disease.

"The sad truth is is that there is no cure for Alzheimer's or dementia. No amount of vitamin D or B is going to cure a degenerative disease," she said in a video.

Emma also said it is important for people to continue to speak about dementia as "there is value in prevention."

"I do think that it is important for us to be having this conversation about brain health.

Emma Heming Willis said there is no cure for her husband (emmahemingwillis / Instagram)

She said it's important to talk about brain health (emmahemingwillis / Instagram)

"You know, when I go to my doctor, my doctor is talking to me about the importance of my breast health, my heart health, but he's not having that conversation with me about my brain health."

Emma said doctors should be speaking to young women in their 20s about how to look after their brains, instead of leaving it "too late".

She added: "I think we should be talking about our brain health so much more than we do."

Emma's comments come after she watched Alzheimer's Research UK's new video campaign which features Succession star Brian Cox.

She's supported Bruce Willis throughout his dementia battle (Getty Images for Film at Lincoln Center)

Emma has kept fans updated on her husband's condition (Getty Images)

In the video, Brian - who lost his brother and brother-in-law to the disease - said dementia "threatens everything".

In response, Emma said: "So the Alzheimer's Research UK has just come out with their new video campaign for a cure and their spokesperson is Brian Cox.

"The video is really hard to watch, but the facts are the facts."

She finished her video with a powerful message: "One in two people will either develop dementia, care for someone with dementia, or both. Predisposed or not, we're all at risk.

"So, I don't know if you know this, but women make up two thirds of the world's dementia patients and that's just staggering to me. I'm not sure why no one is talking to us about that.

"So, I'm just throwing it out there and I think it's so important for us to talk about dementia. I know it's not the sexiest conversation, no one wants to talk about it, but it's an important one."

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