I lost 16½st so I could get married.

SQUEEZING into her dress usually tops a bride-to-be’s list of wedding worries.

But for 27½st Shanna McCormick, just living to see her wedding day was the main concern.

For most of her adult life, Shanna had been in and out of hospital, suffering with life threatening asthma attacks. Doctors warned the strain of her obese body would kill her if she didn’t lose weight — and fast.

Determined not to be a fat wife to her boyfriend of 14 years Dan Dimmock, Shanna called off their engagement to embark on a strict two-year weight-loss plan.

Only after shifting 16½st and dropping 18 dress sizes was she ready to walk down the aisle.

Shanna says: “I had been told for years that my life was at risk because of my weight, and out the other.

so it went in one ear “I was immune to hearing it because I’d heard it for so long, but it was different for Dan.

“He was worried sick.

Sometimes he couldn’t sleep at night because he BEFORE: thought something would happen to me.

“He used to check to see that I was still breathing in the middle of the night.

“The truth is that, at my biggest, I didn’t have a future. Doctors warned me I would die if I didn’t lose weight, so what was the point in planning a wedding? “I might not have even been there to see it.”

At 5ft 6in, Shanna’s life was in constant danger and she admits she can’t remember a time when she was not overweight.

At primary school she was the biggest girl in her class and she was already obese by the time she moved to secondary school.

Conditions linked to her weight, including eczema and asthma, made her a target for bullies, and she turned to food for comfort.

By the time she met Dan aged 18, Shanna was living on crisps, bread and pizza. She was a size 20 and weighed 22st.

Though he was slim, her weight crept up to its 27½st peak as their relationship progressed. In 2007 she spent nine days in intensive care when she suffered a severe asthma attack which doctors blamed on her weight.

Shanna, 31, says: “I was offered weight-loss surgery but was too scared of dying on the operating table, because my weight made the anaesthetic a risk.

“I knew something had to give but I didn’t know how to make the change.”

In 2010 the couple became engaged for the first time. But it soon became clear there was no way they could plan their big day with Shanna’s health problems.

Her frequent visits to hospital meant that it would have been very difficult to set a date and stick to it.

Shanna admits: “I wanted nothing more than to marry Dan but I couldn’t stand the thought of him becoming my carer as well as my husband.

“My size was ruining everything. Now it had even ruined my engagement and stopped me marrying the man I loved.”

It was seeing Dan’s fear and uncertainty about their future together that finally forced Shanna into action and she vowed to stop overeating.

But because of her unhealthy relationship with food and several failed attempts with conventional diets, she opted for a meal replacement plan in order to avoid even the slightest temptation.

Shanna signed up to the Cambridge Weight Plan in August 2011, which allowed her to have four products a day, including a range of milkshakes, nutrition bars and soups.

To her surprise she found it easier to stick to than the calorie controlled plans which had failed in the past.

She lost 9lb in the first week. Shanna recalls: “It was not easy  start with and I missed food terribly, but after a few days I got into the zone and never wavered.”

In the first year she lost an impressive 8st and saw her health improve dramatically.

She explains: “The asthma attacks become less frequent and I wasn’t relying on medication all the time.”

Shanna lost another 8st the following year and reached her 11st and size 12 target in March 2013.

For the first time, she could look in the mirror with pride.

Shanna, who has maintained her target weight, says: “I loved being able to shop anywhere I wanted but what I really loved was seeing the peace of mind it gave Dan.

“It was worth all the hard slog. And looking in the mirror at the new slender me was a joy. I never thought that would happen.”

So much so that when Dan popped the question again on an Los Angeles beach last June, Shanna did not think twice about accepting and getting on with the planning.

She says: “He went down on one knee with a gorgeous vintage platinum ring.

“I loved it but I had to have it made smaller when we got back home because I had lost even more weight.”

But the biggest compliment came when a friend of the couple, who are from Manchester, failed to recognise her. Shanna, who is now a fully trained weight-loss consultant helping other women reach their goals, says: “I was sitting there chatting away to him when it dawned on me that he didn’t know who I was. When I told him it was me he just did not believe me. It was a huge compliment.”

As well as planning their wedding in Las Vegas next year the couple have also bought their dream period home to renovate.

Shanna says: “It will take us years as it needs a lot of work, but it’s something I can commit to now I’ve lost the weight.

Dan says: “I used to think the radical before and-after weight-loss images in glossy magazines could never be true until I watched Shanna do it for herself.

“I am very proud and love her to bits.”

For more information, see cambridgeweightplan.com

Diet before. BREAKFAST: Nothing. SNACKS: Two bags of sweets and fizzy drink. LUNCH: Fish and chips. SNACK: Cans of fizzy drink with more sweets, chocolate and crisps. DINNER: Chinese takeaway plus several glasses of wine or cider, and more sweets.

Diet after. BREAKFAST: Flour-free pancakes with raspberries or a Cambridge shake. SNACK: Fruit and bottle of water. LUNCH: Tuna or chicken salad with water. DINNER: Omelette with green salad and water. SNACK: Bag of hazelnuts with water.

‘My size ruined everything’ ‘Looking in the mirror’s a joy’