Even since her early days on the MTV show, Holly's been open about the struggles she's had with her weight.
And looking at her now, it's hard to believe she was ever the victim of cruel online trolls who ridiculed her for weighing 13st.
But the 23-year-old, who is 5ft 3in, has turned these negative comments into positive action – losing 3st, and going from a size 16 to a size 8 since Geordie Shore's first series in 2011.
Like most of us, Holly's admitted that she'll always have to work hard to maintain a banging bod. In February, she was pictured on Australia's Bondi Beach looking slightly curvier.
But earlier this month, she shared a stunning pic of herself posing and showing off her incredible toned tummy in a black bikini. The post on her Facebook page proved that she is now truly body-confident.
Her new, improved 2016 edition of Holly Hagan's Body Bible, which involves a 12- week carb-cycling regime and exercise plan, is what she credits for her amazing figure.
So how exactly does it work? We give you the lowdown on how to be hot like Holly...
Follow this seven-day regime for three months and Holly and her personal trainer, Ashley Lucas, promise you'll look and feel amazing. Just be sure to repeat each set of exercises twice.
MONDAY One minute of partial goblet squats, one minute of dumb-bell squats, 30 seconds of wall sits, one minute of heel/toe bounces, one minute of dumb-bell lunges.
TUESDAY One minute of burpees with dumb-bell presses, one minute of press-ups, 30 seconds of Turkish get-ups, one minute of Russian twists with a medicine ball, one minute of moving planks.
WEDNESDAY One minute of weighted bridge holds, one minute of lunge walks with weights, one minute of deep squats (toes pointed inwards), one minute of jumping squats, one minute of steps.
THURSDAY One minute of goblet sumo squats, one minute of high dumb-bell step-ups, one minute of dumb-bell squats, one minute of lunge walks with weights, 30 seconds of dumb-bell squats, one minute of jumping squats.
FRIDAY One minute of kneeling partial shoulder presses, one minute of press-ups, one minute of laying dumb-bell extensions, one minute of bicep curls/shoulder presses, one-minute of moving planks.
SATURDAY Two 20-minute cardio sessions either on a bike, treadmill, cross-trainer or step machine.
SUNDAY Rest day.
HOLLY'S DIET IDEAS
HIGH-CARB DAYS (SUNDAYS AND MONDAYS)
On these days, eat high 'clean' carbs: wholegrain pasta, wholewheat bread, sweet potatoes, beans, legumes.
Breakfast Greek yoghurt, oats,chia seeds and berries
Mid-morning snack Handful of nuts
Lunch Skinny club sandwich with wholemeal bread
Mid-afternoon snack Protein shake
Dinner Curried chicken breast with spinach and brown rice
Supper snack An apple
NO-CARB DAYS (TUESDAYS AND FRIDAYS)
No carbs at all for these days!
Breakfast Scrambled eggs with tomato, avocado, red pepper and spring onions
Mid-morning Small pot of cottage cheese
Lunch Beef and veg wrap wrapped in lettuce instead of bread
Mid-afternoon snack Small pot of blueberries
Dinner Cod fillets with asparagus and cherry tomatoes
LOW-CARB DAYS (WEDNESDAYS, THURSDAYS AND SATURDAYS)
On these days, only eat carbs for breakfast.
Breakfast Porridge with blueberries
Mid-morning snack Handful of nuts
Lunch Miso and vegetable soup
Mid-afternoon snacK Protein shake
Dinner Seared steak with fried vegetables
Supper snack Small pot of plain natural yoghurt
We're all human, and we all get tempted from time to time. Plus, if you've worked hard all week you deserve a reward.
"Dieting doesn't mean you have to punish yourself. If you've stuck to your diet and exercise regime 90 per cent of the time, the occasional snack or over-indulgent meal is OK," Holly says.
"For me, I spend all week being good with my diet and exercise, so on a Sunday I allow myself my mum's amazing roast dinner guilt-free! Looking forward to this every Sunday helps motivate me all week."
Holly says these also help her lose weight:
FISH OIL Helps decrease body fat and inflammation, and it's good for the heart, too!
GREEN TEA It burns fat and gives your immune system a boost. You can drink it whenever you like.
MULTIVITAMINS If there are any gaps in your nutrition, this will plug them. Take them in tablet form before a meal.
WATER Dehydration can feel like hunger, so drink at least 1.6 litres a day.
For more information, descriptions of the exercises and delicious recipes, Holly Hagan's Body Bile 2016 is out now, £12.99.
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