One of Kate Middleton's favorite beauty products sells every 20 seconds

A beauty product that Kate Middleton swears by? Sign us up.

We'll have to get in line, though. According to Refinery29, a bottle of a product that the royal mom used during her pregnancy with Princess Charlotte, Trilogy's Rosehip Oil, sells every 20 seconds. Yup, seconds.

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It's not exactly cheap, either -- it's $54 a bottle (though some online retailers, like Jet, sell it for less) -- but it sure seems to have its benefits. As Refinery29 puts it, "It's filled with antioxidants, prevents redness during those dreaded acne breakouts, and even slows down signs of aging."

So that's why the duchess always looks so flawless. Noted.

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This isn't the first time secrets of Kate's beauty routine have surfaced. Late last year, former First Lady Michelle Obama's makeup artist revealed that she uses organic Botox gel, "on the recommendation of Kate Middleton." Rumors have also swirled that the princess uses Nutella spread on her face (though one expert has some reservations about the practice).

Well, whether or not that one's true, we think we'll stick to the Rosehip Oil.

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