The Duke and Duchess of Cambridge have marked World Mental Health Day by meeting young people and hearing their stories of how they battled the issue and are now helping others to do the same.

Kate and William looked visibly moved as they spoke to people about the stigma associated with mental health and the importance of the work of charities like Mind.

They started their visit to Harrow College in north-west London by sitting with young women who told of their personal experiences of dealing with mental health issues and who now volunteer with the anti-stigma campaign Time to Change.

It was the Duke and Duchess of Cambridge's first joint engagement in support of mental health issues.

William asked one volunteer: "What made you get involved do this as a vocation, almost?" Nikki Mattocks, 18, replied: "For me it is because, for years - I have experience of hearing voices - and I never really felt there was a positive role model out there.

"When I said that I was hearing voices, I was told that I must be a murderer.

"For me it is really important for people to know that we are just normal, average people."

The Cambridges also heard from 21-year-old Jessica Kwamin who explained that she had overdosed in the classroom, and had subsequently been expelled.

She added: "My parents are from Africa and in Africa it is such a taboo subject - mental health - because you can't see it, it isn't real, you should be a bit stronger than that."

Kate asked her: "Do you feel that if help had been there earlier, that you would have accessed it earlier? Or did it come to the pushing point?"

Miss Kwamin, from Gravesend in Kent, replied: "I don't think the help would have come to me if I didn't come out and find it."

Nosa Iyobhehe, 25, spoke of how she had battled with low confidence for years, and how working with others and helping them had also helped her.

Addressing the Duchess, she said: "I know Kate, that you did history and art. Where I am from in Africa, they don't accept art as something viable.

"But now I am accepting my strengths and pursuing a career in hair dressing."

Wearing a black and white Tory Burch dress that she first wore in New Zealand last year, Kate replied: "That's fantastic."

Emma Peacock, 19, was eight when she was misdiagnosed with ADHD. She actually suffers from bi-polar, a diagnosis that didn't come until she was 16.

She said: "I made the mistake of telling my friends first. That was not a good idea. Because they didn't understand, they stigmatised it and I was excluded."

The Duchess asked Emma if she'd found it hard to tell her mother, Nadine, who was also at the event. "Did you find it hard to tell your mother about it, not wanting to worry your mother? I always find you never want to worry your family about anything."

Emma said: "I was so scared my family would worry, you always want to protect your family so I found it really hard."

Kate asked Nadine: "From a mother's perspective, how has it affected you?"

Nadine told her: "When your child is going through such difficulties and anxieties, and struggling with mental health, it is heartbreaking. A lot of her friends wouldn't talk about it because it was taboo."

Kate asked the group: "Are schools willing to listen and understand the concept of young people struggling with mental health?"

William then shook his head as he listened to Emma Peacock reply: "When I got ill, I had to go into hospital. My school wouldn't let me back in because they were worried about contagion, and my grades not being good enough. They didn't want to be the school who had "the issues".

At the end of the session, William addressed the group, saying: "I could sit here and talk to you for hours. Thank you so much for sharing your stories with us.

"You are being incredibly brave doing this. I know it's not easy for you re-living your experiences again and again.

"If we can get more young people talking, and coming through with their experiences, then we can really get mental health to the fore, which is where it should be and what we need to do."

Kate told the group: "I keep thinking about what else we can do and how we can raise awareness. Keep the ideas coming. We think it's so important, so really well done for being ambassadors. Talking about mental health is so important."

Jessica said after the session: "They are so high profile, you feel that whatever they say, people will listen to. If they can get people talking about mental health, it will 100% help with the issues."

The Cambridges also took some time to sit in on brainstorming sessions involving people with a history of mental health issues talking to others about their experiences.

Unable to contain her excitement 17-year-old Ariana Madlani-Kotecha told Kate: "My mum is a really big fan of yours."

Kate responded: "Oh is she? Say 'hi' to her from me."

The Duchess's presence in the room was very exciting for many who beamed from ear to ear as she asked about how they became involved with Mind and the Time To Change anti-stigma campaign.

In the middle of explaining how the sessions worked, student Fouzia Mohammed said: "Oh my God, it's so nice to meet you. It is amazing to meet you."

Kate shook her hand and replied: "It is amazing meeting you, what you are doing is amazing. You guys are going all the hard work."

Following the Mindkit session, Kate and William took part in a relatively informal reception talking to groups of people involved with the work of Mind.

Refusing to take any cake, William joked: "I am not allowed cakes. Also it is very difficult to talk to people when I am eating cakes. I would cover all your tops with chocolate. It is not very good. "

Addressing another group of volunteers, William spoke of the need for mental health issues to be addressed about more openly. He said: "Without hearing from people it is very difficult to come up with a plan. You are very brave and what you are doing is fantastic."

The visit ended with the couple listening to a speech by Vithuja Balasingham, 19, a Time to Change volunteer. She was first diagnosed with depression aged 12 and Kate looked visibly moved listening to her speak.

She said: "Since then I've been sectioned and hospitalised. I've hit the worst of the worst where life no longer felt a viable option.

"At home, my family didn't understand, I had a perfect life so why was I so miserable. I've had peers calling me an attention seeker, messages on formspring telling me to kill myself, nurses referring to me as the sectioned girl.

"When I first found out about time to change I was shy about getting involved given the stigma and discrimination I had faced.

"I am now a young involvement worker, youth panellist and a champion for Time To change...I'm here today to celebrate how far we've come but to remind people that it is okay to talk without being afraid or ashamed."

At the end of the reception, Kate drew laughter from those gathered, as she jokingly inquired whether William wanted to accept the bouquet she had been presented with.

Mental health charity Mind provides advice and support to empower anyone experiencing a mental health problem.

Every year, Mind in Harrow helps over 7,000 local people with assistance from over 100 volunteers.