'I wondered how big my coffin would be - it made me lose 11st in 18 months'

When Alison Berry discovered she was about to become a grandmother, it dawned on her that it was time to shed the pounds. The former dinner lady had spent years indulging in whatever she fancied and shunning exercise.

"I had three under five and I lost no baby weight in between. I just felt content and carried on living my life," Alison recalls. "I had my family and everything was hunky dory, but my mum and dad would tell me I could do with losing a bit of weight. They were right, and I would try. I had a go at shakes, pills, hospital diets, crash diets, you know it. They did work, but then I would give up or get bored and then regain it."

By the time she hung up her apron a decade ago, she tipped the scales at 22 stone, plagued by bad eating habits. "As a teen I couldn't swap clothes with my friends as I was bigger than them all," shares Alison, 66, from Hebburn, South Tyneside.

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"I'm a real adrenaline junky and I love rides, but I remember having to get off one at a funfair because they couldn't get the safety bar down. And my family would plan days out where I could sit down and rest. Options would be discarded if there was nowhere for me to sit down."

A particularly distressing memory for Alison was at a friend's birthday party, where she chose a small plate of food after overhearing a stranger's remark about beating her to the buffet before she 'hoovered up' everything. At that moment, Alison believed weight loss was beyond her reach, but in hindsight, she recognises she simply didn't put in enough effort.

"I used to have a full-fat can of coke with a handful of chocolate bars for breakfast and would graze all day at work, eating steamed pudding and custard," she says.

"The only exercise I got was walking to the toilet or walking to the fridge. I was dying to be a grandmother, but when my daughter-in-law was due to go back to work after having Joseph and she asked if I would look after him for a couple of days a week, it was all I wanted to do.

"I wanted to take him to the park, take him swimming and get on the floor and play with him, and then I realised I could do none of these things because I couldn't even bend over to clip my toenails."

Alison was also battling serious health problems. She'd received a diagnosis of diverticulitis, a bowel condition that triggers abdominal pain, diarrhoea and constipation.

"It was like a disability to me," she says. "I had to go to the loo 40 times a day and I ended up in hospital one morning. My kidneys were failing and the doctors in the hospital told me I was lucky I'd come in when I did because otherwise I wouldn't be here anymore.

"I spent three weeks in hospital and when I got back, I sat at home feeling sorry for myself, thinking that I was going to die, overweight and unhappy. I used to lie in bed at night crying, thinking how big my coffin would be and who would carry it."

Alison's close call with death was a stark wake-up call that she had much more to experience in life, and in October 2014, she dived headfirst into dieting. She signed up with Slimming World and started getting off the bus early to walk extra miles.

"At my first meeting the lady put me on the scales and told me to read out my weight. When I did, she told me: 'That's the last time you'll ever say that,' and something clicked."

Initially sceptical, Alison quickly grew to love the supportive atmosphere at Slimming World, and her efforts paid off immediately with a 5lbs loss in the first week. As time went by, the pounds kept dropping, and Alison, who still indulged in occasional treats, became truly dedicated to her health journey.

Alison's transformation was so dramatic that people began to worry she might be suffering from an undiagnosed illness. Even her doctor was concerned enough to order a scan for cancer.

After the results came back negative, he congratulated her, saying: "Alison, congratulations. You've saved your own life."

She shed an incredible 11 stone in just a year and a half, has maintained a steady size 11, splurged on a brand-new wardrobe, and is now embracing life's thrills, engaging in fire walks, zip lines, and tree-top assault courses. Moreover, Alison has been able to come off all her medication, and her previously 'ridiculously high' blood pressure is now perfectly normal.

"Losing the weight wasn't easy, but it was worth it. And I was very determined," shares Alison. "I used to be afraid of walking to the shop in case people laughed at me, but now I walk with my head held high with a big smile on my face. I am a lot healthier too and I manage my condition well, knowing what and what not to eat. I'm able to look after my grandchildren, which makes me so happy, and I feel amazing."