Tawnell Hobbs, Rob Barry and Yoree Koh:

Some included tips about taking in less than 300 calories a day, several recommended consuming only water some days, another suggested taking laxatives after overeating.

Other videos showed emaciated girls with protruding bones, a “corpse bride diet,” an invitation to a private “Christmas-themed competition” to lose as much weight as possible before the holiday and a shaming for those who give up on getting thin: “You do realise giving up after a week isn’t going to get you anywhere, right?…You’re disgusting, it’s really embarrassing.”

On Thursday, several days after the Journal sought comment for the findings detailed in this article, TikTok said it would adjust its recommendation algorithm to avoid showing users too much of the same content, part of a broad re-evaluation of social-media platforms and the potential harm they pose to younger users. The company said it is testing ways to avoid pushing too much content from a certain topic to individual users—such as extreme dieting, sadness or breakups—to protect their mental well-being.