William's great British cake-off: Prince reveals he has been banned from eating sweet cakes as he marks World Mental Health Day with Kate

Her svelte figure is the envy of women everywhere.

And it seems the Duchess of Cambridge may also be encouraging her husband to watch his waistline – after William revealed he has been banned from eating cake.

William made the confession as he and Kate marked World Mental Health Day yesterday by visiting youngsters who have battled back from mental health problems to help others cope with similar issues. 

It seems the Duchess of Cambridge may also be encouraging her husband to watch his waistline – after William revealed he has been banned from eating cake. Above, the royal couple marking World Mental Health Day

It seems the Duchess of Cambridge may also be encouraging her husband to watch his waistline – after William revealed he has been banned from eating cake. Above, the royal couple marking World Mental Health Day

As he walked past a trestle table holding a display of cupcakes at the event in Harrow College in North-West London, William said: ‘I’m 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’s not very good.’

In a previous interview, Carolyn Robb, a former personal chef to Prince Charles, revealed the Prince’s boyhood love of cake: ‘Princess Diana was very keen that her boys should have a really healthy diet, but they had treats too.’

During their visit yesterday, the Duke and Duchess of Cambridge chatted to volunteers with the charity Mind and the anti-stigma campaign Time To Change.

As he walked past a trestle table holding a display of cupcakes at the event in Harrow College in North-West London, William said: ‘I’m not allowed cakes'

As he walked past a trestle table holding a display of cupcakes at the event in Harrow College in North-West London, William said: ‘I’m not allowed cakes'

The Duchess beamed as she met with young people who have overcome mental health issues at an event in Harrow today

The Duchess beamed as she met with young people who have overcome mental health issues at an event in Harrow today

Kate pulls a face at her husband as she clutches a bouquet of flowers at the event hosted by charity Mind

Kate pulls a face at her husband as she clutches a bouquet of flowers at the event hosted by charity Mind

The Duke and Duchess of Cambridge, pictured during their visit to Harrow College in north west London today

The Duke and Duchess of Cambridge, pictured during their visit to Harrow College in north west London today

Get the royal seal of approval in Kate's Tory Burch dress

There are no shades of grey when it comes to the Duchess of Cambridge’s meticulous style. In matter of fact, it’s pretty black and white.

Making an appearance for World Mental Health Day alongside husband Prince William, Kate looked impossibly demure in a knitted monochrome dress by American fashion designer Tory Burch.

Welcoming in the autumn/winter with the thick textured creation from Burch’s Resort 2014 collection, Kate kept things classic with her trustee pair of Stuart Weitzman black court shoes and a Mulberry clutch bag.

The short-sleeved open-knit dress is designed to streamline the figure, and most certainly announced Kate’s elegant waist with its cinched-in fit. The flattering knee-length hemline makes it a key ladylike piece for any day-to-night occasion in the colder months, and would look just as great under a timeless black overcoat or blazer.

Unfortunately, Kate’s dress is not available to buy since it is past season, but you can shop the current collection at Net-A-Porter with a click to the right. It is one of the Duchess’ favorite brands after all!

Alternatively, emulate the look with our top options from the likes of Missguided, Shoptiques and more in the edit below.

* PRICES MAY NOT BE AS ADVERTISED

Both appeared visibly moved as the youngsters spoke of the stigma associated with mental health problems. 

Asked by William why she had become involved with the campaign, Nikki Mattocks, 18, said: ‘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.’

Kate smiles as she hears from young women involved with the charity Mind and Time to Change campaign

Kate smiles as she hears from young women involved with the charity Mind and Time to Change campaign

Kate shakes hands with a group of young girls who were at the event to share their experiences with the couple

Kate shakes hands with a group of young girls who were at the event to share their experiences with the couple

Kate sweeps her hair behind one ear
She gets stuck into a brainstorming session with the youngsters

Kate sweeps her hair behind one ear (left) as she gets stuck into a brainstorming session with the youngsters

Prince William got stuck into the interactive session where he heard from a group of young people who had been affected by mental health problems

Prince William got stuck into the interactive session where he heard from a group of young people who had been affected by mental health problems

The Duchess heard from a mother's perspective how it feels for a child to be affected by mental health

The Duchess heard from a mother's perspective how it feels for a child to be affected by mental health

The Duke and Duchess of Cambridge, pictured during their visit to Harrow College in north west London today
Prince William and the Duchess were there to meet with young people who have been affected by mental health issues

Prince William and the Duchess were there to meet with young people who have been affected by mental health issues

At the end of the visit, Kate – who wore a £258 Tory Burch dress previously seen during last year’s tour of New Zealand – provoked laughter as she jokingly asked William whether he wanted to accept the bouquet she had been presented with.

A Buckingham Palace spokesman said of the Prince’s cake comment: ‘I think probably it was a joke by Prince William. 

'I know he doesn’t eat when he is talking to people as it can be awkward.’ 

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