On Monday, Dec. 29, Kim Kardashian -- the self-proclaimed Instagram selfie queen -- shared several black and white photos of herself and her loved ones posing at the photo booth for her mother Kris Jenner's "Better not Pout" holiday party.

Among the photos posted on her Instagram account was a shot of the eldest Kardashian daughter smiling with family friend Shamari Maurice along with a caption explaining why she doesn't often smile in photos.

Kim explained that she doesn't smile because she believes that smiling "causes wrinkles."

Check out the rare Instagram photo of Kardashian smiling below.

Kardashian's vain reason for not smiling in photos might not come as a shock since she is known to take on drastic measures to maintain and upkeep her physical appearance and beauty. Last year in March, Kim Kardashian sparked a wave of controversy after she was filmed undergoing a "Vampire Facelift" on a past episode of "Kim and Kourtney Take Miami." In the episode, Kim Kardashian is shown with a face full of her own blood injected back into her skin to allegedly reverse the signs of aging. At the time, the New York Daily News reported the procedure "draws blood from the patient's arm with a needle and separates the platelets into a platelet-rich plasma (PRP) using a centrifuge. The plasma is then combined with Restylane or Juvederm and then injected into the face to stimulate collagen production to create new skin and to remove fine lines and acne scars." Earlier this year in August, another one of Kardashian's cosmetic procedures made headlines again after she posted an Instagram photo of herself sporting a waist trainer in attempt to lose her baby weight weight faster and obtain a "perfect" hourglass shape.

Though many celebrities have flocked to the waist training trend, online critics slammed Kardashian for her vanity and apparent obsession with losing weight.

"Not the way to go @kimkardashian. If u wanna do it don't plaster it all over Instagram, etc for impressionable females to see, not ur best move #loveurbody the way it. Is," Instagram user nikkif65 wrote.

"North will have eating and body dismorhpia disorder...Please start being kind to girls and the future of our beauty standards. This is beyond ridiculous - your great natural...own-it don't fake/shape it," another Instagram user ciaokittykitty wrote.

The Huffington Post also weighed in on the waist training trend and spoke with bariatric physician Jyotindra Shah who claimed that the waist training corset would potentially bruise the skin along with the liver, spleen and kidneys.