How often have you wanted to shift those stubborn extra kilos, that no matter what diet you try, just won't budge?

Well now there's a brand new diet that could be the key to fast and effective weight loss. It claims you can lose up to five kilograms in just a fortnight.

With the help of three mums who all wanted to shed their baby weight, the two week turnaround was put to the ultimate test.

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All three women admitted they snack on kids’ dinners and lollies all day. Therefore sticking to a regimented eating plan of around four meals each worth 400 calories, and three small snacks - like a glass of milk or an apple, was going to be a challenge.

Prevention magazine food editor Judy Davie says the diet’s meals are substantial serves, but with more protein than carbs, designed to fill you up, not out.

"It looks like a very big breakfast for someone that's on a diet,” Davie said. “Breakfast is the biggest meal of the day. In this meal for example there is five egg whites, whipped up into an omelette, some cheese and a wholemeal pitta, added to that is some banana for energy and a low fat yogurt.”

One diet step at a time

According to Davie " it's important to have protein with the main meal, so breakfast, lunch and dinner have a substantial amount of protein. Studies have shown that diets with increased calcium are good to encourage weight loss as well, so it's good to put dairy and calcium in most of your meals as well."

Then there's the exercise program. It includes thirty minutes of workouts, six times a week. It’s rigorous but super effective, and most of it can be done at home.

• push-ups
• lunges
• the dreaded plank
• running
• hand weights
• power walking.

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All are designed to speed up your metabolism, and break down fat fast.

Fourteen days after their weight loss mission began, the three mums have all lost weight.

Bec dropped almost two and a half kilos - from 70.5 to 68.2. She admits she found the diet hard to stick to every mealtime.

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Victoria went from 60.6 kilograms to 57.3.

The biggest success, Jacquie, almost reached the target of five kilos, and says she didn't stray from the diet or the exercise plan once.

Natalie Filatoff, editor of prevention, believes this diet is achievable even if you're time poor. You just need will power and motivation.

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"Collectively the three women have lost over ten kilograms, but one woman has lost 4.8 over the two weeks, which I think is terrific," Filatoff said.

"It’s a great achievement. Even better is that they all felt incredibly well, and they actually enjoyed it."