In case you've ever wondered why Kim Kardashian is not huge on smiling in photos, she's finally revealed her reasoning, and it has everything to do with the anti-aging process.

During Kris Jenner’s annual Christmas Eve party, photos of the Kardashian clan popped up all over social media. One photo in particular sees Kim with Kendall and Kylie’s dear friend, Samari Maurice, and in it we see something from Kim that feels like the witnessing of a rare diamond being discovered: Kim is full on laughing.

Fans have noted that Kim is not huge on smiling in photos, though she and her sisters are constantly cracking each other up on ‘Keeping Up With the Kardashians.’ Kim is totally aware of the how fans perceive her smiling (or lack thereof) and posted the photo on Instagram, saying: “See I do smile… even laugh on occasion. Not too often though because it causes wrinkles."

So there you have it, guys: In order to preserve her smooth, baby-like skin and keep it free of wrinkles, Kim chooses not to smile in photos.

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