The best celebrity weight loss transformations that are actually realistic

Sunrise's Samantha Armytage has dropped 10kg since becoming Weight Watchers' celebrity ambassador by eating a diet rich in fruit and veggies, as well as getting active with a personal trainer and walking her beloved dog Banjo.

Karl Stefanovic looked dashing at the 2019 TV WEEK Logie Awards. He kick started his health journey in 2018 when his doctor warned him that he needed to make some changes to his physical health. "I was fatter than I thought," the former Today Show host confessed on Instagram.

Tziporah Malkah confessed to undergoing lap-band surgery, but it didn't work for her. But after losing 12kg on I'm A Celebrity Get Me Out Of Here, the motivated Aussie made a number of lifestyle changes and started working with a personal trainer, shedding an impressive 50kg.

Pop princess Britney Spears is looking toned and trimmed. These photos were taken 10 years apart and if you check out the Toxic singer's Instagram page, you can see her incredible fitness regime that involves plenty of cardio and weights.

Sarah Ferguson was cruelly nicknamed the "Duchess of Pork" by the UK tabloids due to her struggles with her weight. But the royal mum-of-two, who has also represented Weight Watchers, is looking happier and healthier than ever and told the Mail Online that she eats tomatoes, egg mayonnaise and mandarins to keep slim.

Australia's Got Talent's Ricki Lee has always been a beauty, but her 30kg weight loss over eight years blew us away! Her secrets include eating organic veggies and drinking three litres of water a day, but she doesn't forget to treat herself. "Once a week, I have a cheat meal – either a burger and fries, spaghetti bolognese or carbonara," she previously revealed.

Sam Frost has changed in many ways since she won The Bachelor. Australia's sweetheart has lost 12kg since she first graced our screens and admitted that she eats a strict Rachael Finch-inspired diet, but still allows herself the occasional 'cheat meal' adding, "I try to do 20 minute workouts every day, but realistically, I do them every second day."

The Voice's Guy Sebastian admitted that he suffered from fat shaming in his youth, but wowed everyone with his Men's Health cover. To achieve those muscles, Guy went on a strict keto diet for two weeks, before introducing healthy carbs like brown rice, sweet potato and broccoli into his diet. Lactose-intolerant Guy drank no milk or alcohol either and drank two litres of water per day.

Speaking of The Voice, Australia's first ever winner Karise Eden has had a similarly amazing weight loss. The singer lost 21kg in 12 months following the birth of her son.

She's known for her indulgent desserts, but Nigella Lawson lost an impressive 12kg over three years and looks stunning. The MasterChef guest judge told Good Housekeeping, "I wouldn't want a life where I lived on chia seed pudding, just as I wouldn't want to live where I lived on eggs Benedict or steak and chips."