The 35-year-old is following the Atkins Nutritional Approach - which focuses on reducing carbohydrates and sugar in your diet.
And the results are certainly starting to show, with the star posting a snap of her glowing, flawless complexion since she made the changes in her diet.
Kelly announced she’d started to see her body alter after over-indulging at Christmas, as well as snacking while she filmed US sitcom One Big Happy.
Evidently unhappy about the way things were going, the model decided to take radical steps to get her body back.
Captioning her bare-faced snap, Kelly wrote: ‘Day 12 of #NoSugar #NoCarbs My Skin is the best it’s been in ages. No Fine lines or Blemishes!! Healhy Glow #MyAtkins is really paying off #Ad #Truth #NoFilter #NoMakeUp.’
Earlier, Kelly had been sharing some bikini clad snaps of her in her modelling heyday, showing off her incredibly toned body.
**Want some Diet Inspiration? Check out our Atkins recipe gallery below.
**
Atkins diet: Your three day kickstart plan
1 of 14RECIPE: Cheese and spinach omelette
This omelette is easy and quick to prepare and will set you up for the day ahead.
2 of 14RECIPE: BLT wrap
This low-carb breakfast gives you a bit of savoury and sweet to wake up to in the morning. Great for the Atkins diet.
3 of 14RECIPE: Greek yoghurt with berries and almonds
This is a super simple but delicious breakfast, ideal for the Atkins diet.
4 of 14RECIPE: Broccoli and stilton soup
This healthy soup tastes decadent but is still low carb and low fat - the best of both worlds!
5 of 14RECIPE: Grilled chicken salad
A fresh and flavoursome salad - add a handful of strawberries for the perfect Atkins lunch.
6 of 14RECIPE: Italian lunch
A slice of the Italian Riveria - on a calorie budget. The perfect salad to take into work or enjoy at home.
7 of 14RECIPE: Chicken and veg stir-fry
A low-carb favourite that's quick, easy and bursting with flavour.
8 of 14RECIPE: Mediterranean roasted veg
A mouthwatering dinner that's big in nutrients and ideal for an Atkins diet.
9 of 14RECIPE: Grilled salmon with asparagus
A light, zesty dinner full of superfoods!
10 of 14Snack
Try 2 handfuls each of raspberries and blueberries with 1/2 a pot of greek yoghurt for a sweet treat.
11 of 14Snack
1 hard-boiled egg with lettuce, tomato, cucumber and 1tbsp light mayo make a tasty snack.
12 of 14Snack
6 tbsp guacamole with 3 celery sticks is great between meals.
13 of 14Snack
Pick 9 walnut halves, 12 pecan halves or 21 unsalted almonds for something to nibble on.
14 of 14Snack
2 celery sticks filled with 5 tsp of peanut butter will help keep you going.