Kardashian fans are slamming Kim Kardashian for a photo she posted on Instagram.

In the photo, the 33-year-old reality star poses in front of a mirror sporting a waist trainer. She captions the photo with a series of hashtags that read, " #hourglass, #waisttraining, #nophotoshopnecessary #whatawaist.com."

Kardashian joins a long list of celebrities "training their waists" to obtain a more defined hourglass figure using a waist training corset created by waist training guru Premadonna.

Premadonna, whose Instagram handle is Predmadonna87, prides herself on having what she calls "the most aggressive waist trainer" that allows her clients to lose "2 inches off their waist in a week."

On Instagram, Premadonna writes her story of how she came to create the waist trainer and the success she's had since using her own product.

"Being A Mother Of Two Children I understand how important it is to want to lose excess fat due to childbirth," she writes on Instagram.

"SO I focused strategized a plan on how to get sexy again & I like to rush so u knew ,I needed something Fast..At the time I couldn't afford SURGERY ..(And I didn't want Any ugly scars from it EITHER)my c-section cut is enough..So I knew I couldn't take any short cuts..I was also just two busy being a single mom, Working 2 jobs I didn't have time to even exercise let alone I was LAZY ...So i applied what I know, I begin #waisttraining ..I lost 2 inches in a week everyone at my job asked what I was doing ..(But me being the business woman it am I didn't tell them..) instead I started selling My secret ..Also the celebrities best kept secret & the rest is history."

Though many celebrities have flocked to the waist training trend, online critics are slamming 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.

In addition to being highly uncomfortable, waist training is known to have a series of serious side effects, The Huffington Post reports.

"Putting this corset tight on the body could bruise your skin," bariatric physician Jyotindra Shah to THP last October. "People might put it so tight that the liver, spleen and kidneys could get bruised."

Kim Kardashian has yet to respond to the waist training backlash.

What are your thoughts on Kim Kardashian's decision to waist train? Share your comments below.