Not what you think it would be.
If you're a lipstick obsessive, like most of us at MC HQ, you've probably swiped on hundreds of lipstick shades during your lifetime. Summer calls for shades of coral, popping orange and neon pink, while winter conjures up a desire for deep burgundy, rich violet and red brick. But, if we were to ask you what you thought was the most popular colour of lipstick, we wouldn't be surprised if you said a classic red. What is surprising is that it's actually not. In fact, the most popular lipstick shade is so niche, it even come from a particular brand.
The hue in question? MAC's Lipstick in Watch Me Shimmer. Part coral, part pink, part glossy, the shade itself reminds us of a juicy watermelon, making it the perfect colour for a hot summer's day. But, there's a hitch.
Like most of MAC's amazing shades, this particular one was a limited edition for 2012 and although it made a quick reappearance in 2015, it's now almost impossible to track down.
Thankfully, there also happens to be a whole Pinterest page dedicated to the best Watch Me Shimmer dupes, so if you didn't get your hands on one last year, you can still get the look with these...
Maybelline Color Sensational Vivids in Shocking Coral, £6.99, boots.com
Melted Liquified Long wear Lipstick in Melon, £19, toofaced.com
Collection Deluxe Lip Lacquer in Show Off, £4.19, superdrug.com
After your signature shade of red lipstick? There's a quiz that matches you with the best ones for you – find your perfect red here
