A thin, dark-haired girl stands in her bedroom showing off her bloated stomach. A funny audio screams over her video, “You skinny bitches are evil and you need to be destroyed!” Then she transitions to another clip, one where her flat stomach has returned. “And them big fat bitches will burn in hell,” the rest of the sound plays.

The contradictory messages of this post by @supercoollibragirl—which has two million views—are the subject of debate among its more than 4,000 commenters who argue about its intent: Is the young woman humblebragging about her thinness? Or putting herself down for being fat? Some say they love her “confidence” and “y’all are just jealous, she looks great.” Others reassure her that “she’s allowed to have her own insecurities.” Then there’s an overall consensus of wanting “this trend to be buried.”

But what is this trend?

It’s one of the many so-called “body-checking” trends that have plagued social media sites for years and now can be seen on TikTok. Body checking is when users draw attention to the size and shape of their bodies, usually as a way to show off their thinness. In one of the most infamous body-checking trends from 2013, people stood with their knees together to show they were skinny enough to have a “thigh gap.” A decade ago, Tumblr and Instagram became notorious sites riddled with posts that glamorized anorexia and disordered eating. History repeats itself, and old trends have resurfaced to a fresher and naive audience on TikTok with #bodychecking reaching 5.5 million views on the platform.

What is interesting about TikTok’s new wave of body checking is that these videos often try to mask what they’re really about, burying their messages in irony and sly humor. Tonally, it’s very Gen Z, which accounts for 60 percent of TikTok’s users, who are between the ages of 16 and 24.

The problem of social media’s impact on young people’s body image blew up in the news in 2021 with the revelations of the Facebook whistleblower, Frances Haugen, a former product manager for the company. “Thirty-two percent of teen girls said that when they felt bad about their bodies, Instagram made them feel worse,” a leaked presentation slide said. Facebook knew that Instagram was making eating disorders and suicidal ideation worse in teenage girls, Haugen told 60 Minutes.