And these days it looks like she's turned to something far less painful and expensive than needles to plump up her pout!
The Geordie Shore favourite has admitted to having both lip and cheek fillers in the past, but it seems those days are numbered after she not only hit back at her lip critics with a no make-up selfie back in May, but also included the following comment about her 'au naturel' lips.
"Train selfie #NoMakeUp I look like a little boy sometimes THIS IS MY LIPS WITHOUT A POUT OR LIPLINER BTW. JUST A NORMAL AVERAGE SIZED MOUTH. So leave all the negative comments out please!"
She captioned her photo with no words, however, which left a LOT of her followers wondering what beauty product it was she was using.
Well, fear not, dear Revealers, because we know exactly what it was: namely, Plump It! Volumising Lip Plumper, £19.99, plump-it.com.
Marnie's not the first Geordie Shore star to show her appreciation for this lip plumping gloss, which claims to be able to increase the size and profile of your lips for up to 12 hours with just one application.
Charlotte Crosby, Holly Hagan are also big fans. As are former TOWIE ladies Billie Faiers and Chloe Sims.
ps: We also love Smashbox O-Plump Intuitive Lip Plumper, £18, boots.com and Soap & Glory Sexy Mother Pucker Extreme Plump Lip Gloss, £10, boots.com.
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