Ada Nicodemou's 'mascara face' is one every makeup lover knows too well.

Home and Away actress Ada Nicodemou has proven she is all of us when it comes to mascara application.

The 39-year-old is a self-confessed beauty junkie, but that doesn’t make her exempt from the phenomenon of ‘mascara face’.

Doesn’t ring a bell? Well, watch the mirror closely next time you coat your lashes – or just watch the video above – and you’ll notice it’s almost impossible to apply mascara without arching your eyebrows and opening your mouth.

Ada shared a galler of photos of her mascara face on Instagram, and we love her for it.

#mascaraface #facegoals

A post shared by Ada Nicodemou (@adanicodemou) on

It’s an expression many women will recognise. So what causes us to look so awkward when we apply our favourite makeup?

According to some very reasonable sounding explanations on Quora, the reason is simple.

When you open your mouth, your eyes open just a little bit wider, stylist Phoebe Gavin wrote. This also explains why we would arch our brows – also in an effort to widen our eyes.

Listen: Zoe Foster Blake’s best beauty advice for the time-poor woman. (Post continues after audio.)

Meanwhile, Cristina Cordova theorises that when you’re concentrating hard on something, your jaw tends to relax and open naturally.

Have you ever tried putting on mascara with your mouth closed? It’s harder than it seems.

Whatever the reason, we’re glad not even celebrities can avoid looking a bit silly mid-mascara application.