Bikini-clad Lucy Mecklenburgh and beau Ryan Thomas display shocking weight loss in pre and post Celebrity Island snaps... as she admits to regaining TWO STONE in three weeks

She found love with Corrie star Ryan Thomas during her stint on Celebrity Island.

But Lucy Mecklenburgh's relationship status was not all that changed when she appeared on the Bear Grylls survival show, as she admitted she lost an eye-popping two stone while filming the tough programme earlier in the year.

The 26-year-old health and fitness guru took to Instagram on Tuesday, as did her actor beau, to share before and after snaps from their time on Celebrity Island, with Lucy displaying her incredibly slim post-show body following her gruelling weight loss.

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Ouch: Lucy recently admitted she lost an eye-popping two stone while filming Bear Grylls gruelling survival show, Celebrity Island (pictured before and after)

Ouch: Lucy Mecklenburgh's relationship status was not all that changed when she appeared on the Bear Grylls survival show as she recently admitted she lost an eye-popping two stone while filming the tough programme

Lucy soared to fame in TOWIE's 2010 inauguration where she was the on-off flame of Mark Wright before becoming engaged to Mario Falcone - a romance that ended in disaster after she was unfaithful with Mark. 

She re-branded herself from a drama-attracting reality star to a health maven after leaving TOWIE in 2013 and creating subscription-based diet and exercise plan Results With Lucy, with the company going from strength-to-strength.

As she continued in her foray into television, the brunette beauty joined nine other celebrities in being stranded on an uninhabited Pacific island with basic tools and limited water as they were made to find their own food for Celebrity Island.

Speaking to The Mirror, Lucy revealed she was told by producers she must gain weight ahead of the show due to what was to come - leading to the star gaining half a stone before making her way into the unknown.  

Before: As she continued in her foray into television, the brunette beauty joined nine other celebrities in being stranded on an uninhabited Pacific island with basic tools and limited water as they were made to find their own food and water

Before: As she continued in her foray into television, the brunette beauty joined nine other celebrities in being stranded on an uninhabited Pacific island with basic tools and limited water as they were made to find their own food and water

After: Lucy revealed she was told by producers she must gain weight ahead of the show due to what was to come - leading to the star gaining half a stone before making her way into the unknown

After: Speaking to The Mirror, Lucy revealed she was told by producers she must gain weight ahead of the show due to what was to come - leading to the star gaining half a stone before making her way into the unknown

That was then... Lucy's figure was incredibly slender, as she displayed worringly visible bones and a svelte waist 

That was then... Lucy's figure was incredibly slender, as she displayed worringly visible bones and a svelte waist 

Despite the gain, she admitted she wound up losing closer to two stone - leading to her dramatically slimmed down figure on her already slender frame. 

Taking to Instagram to share a before and after shot in the same bikini and same pose, the businesswoman displayed the vast difference in her shape before revealing she had taken just three weeks to regain the two stone she lost. 

She penned: 'My poor little body!!!! So emotional watching the last ep of #celebrityisland .. I can't believe we did it.. I can't believe I did it what an experience! I will never doubt myself ever again!! 

'Met some incredible people that will be friends for life. So proud of us all!! #celebrityisland #beargrylls #theisland.. PS It only took me 3 weeks to put all my weight back on! I ate ALOT HAHAHHA!!!!'

Following suit: Like Lucy, her boyfriend Ryan Thomas shared a dramatic before and after post to depict his own shocking weight loss having survived Celebrity Island

Following suit: Like Lucy, her boyfriend Ryan Thomas shared a dramatic before and after post to depict his own shocking weight loss having survived Celebrity Island

Beaming: He followed up his post with a snap of himself and Bear Grylls, telling fans that he is 'extremely proud' of himself for lasting on the gruelling show

Beaming: He followed up his post with a snap of himself and Bear Grylls, telling fans that he is 'extremely proud' of himself for lasting on the gruelling show

Her boyfriend Ryan followed suit as he displayed his own shocking weight loss following their stint on Celebrity Island together. Posting a before and after shot for his followers to see, Ryan looks dramatically slimmer. 

He penned alongside the snaps: 'The Final episode tonight everyone. The journey we've been on is indescribable. Not even a television show can put into perspective how mentally and physically we got tested on this island. 

'My before and after is an example of the lack of food, 8 days no eating trying to survive with so little energy. I'm extremely proud of myself and my fellow islanders. Couldn't have done it without you guys.'

Ryan added: 'The reason I love this show so much is because unlike any other there is no winner, it is a matter of survival and not about competing against each other.'

Different days: Lucy founded Results With Lucy in 2014 after discovering unflattering images from a beach holiday where she decided to tone up her figure 

Different days: Lucy founded Results With Lucy in 2014 after discovering unflattering images from a beach holiday where she decided to tone up her figure 

Changing shape: Back in April, Lucy was again showing off a super slim frame at a California event

Changing shape: Back in April, Lucy was again showing off a super slim frame at a California event

Lucy, meanwhile, has spoken about her weight loss to The Mirror and revealed: 'I was told you should get used to eating less and less but then the I was told: "No, no, no you need to put on some weight." So I put on half a stone.

'It was weird because when you're there you don't really feel as thin as you are because you don't have a mirror so you don't really know how tiny you are and then you get back and you realise.

'I must admit it was really nice to indulge. I put on all the weight in three weeks and the doctor was like: "Wow that is some serious eating"'.

Changing shape: Lucy founded Results With Lucy in 2014 after discovering unflattering images from a beach holiday where she decided to tone up her figure (pictured with ex-boyfriend Mario Falcone in 2012)

Changing shape: Lucy founded Results With Lucy in 2014 after discovering unflattering images from a beach holiday where she decided to tone up her figure (pictured with ex-boyfriend Mario Falcone in 2012)

Found love: She found love with Corrie star Ryan Thomas during her stint on Celebrity Island

Found love: She found love with Corrie star Ryan Thomas during her stint on Celebrity Island

Work winter whites with Lucy's broderie dress

Lucy Mecklenburgh stepped out in this dress several months ago now, but we're still obsessing over it.

The layered midi dress is from Australian brand, Bronx and Banco. Love it as much as we do? Shop it now by clicking right.

With a deep V neckline and subtle, sheer lace skirt, this is no boring broderie dress.

Do it like Lucy and add a statement accessory (such as her Launer London bag) for added style points!

Try our edit below for more options inspired by Lucy’s feminine dress. We appreciate it's coming into the cold season now, but there is such thing as winter whites you know! Just add a biker jacket and heeled boots to make it season-appropriate.

Want to steal the style without breaking the bank? Check out our Oasis hot pick for a high street buy that still looks luxe.

* PRICES MAY NOT BE AS ADVERTISED

Lucy founded Results With Lucy in 2014 after discovering unflattering images from a beach holiday where she decided to tone up her figure. 

In a previous Instagram post she penned: 'My before & after photos .. I have never been overweight just unfit, unhealthy & had that annoying stubborn cellulite 2 years ago I started gradually changing my diet & training 3-5 times a week. 

'It made me feel like a completely different person! .. That's why I created @resultswithlucy . I'm so proud that nearly 100,000 women have used my online fitness & health programme resultswithlucy.com to become fitter & healthier with me! It's not a fad diet or a quick fix its about a whole lifestyle change! 

Way back when: Lucy soared to fame in TOWIE's 2010 inauguration where she was the on-off flame of Mark Wright before becoming engaged to Mario Falcone - a romance that ended in disaster after she was unfaithful with Mark

Way back when: Lucy soared to fame in TOWIE's 2010 inauguration where she was the on-off flame of Mark Wright before becoming engaged to Mario Falcone - a romance that ended in disaster after she was unfaithful with Mark

Lucy Mecklenburgh displays weight loss on Instagram

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