Eating disorder charities have issued a warning about a "harmful" diet app that had been promoted on the Apple App Store to over-12s.
Carrot Fit aims "to transform your flabby carcass into a Grade A specimen of the human race" using encouragement in the form of light-hearted abuse.
It said it had helped thousands of users meet their health goals.
But critics said that the app was irresponsible and could trigger eating disorders.
Since the concerns were brought to its attention, Apple has raised the age recommendation on the app's page to over-17s.
"The way they are addressing weight is inappropriate and scary. It's not a healthy body image and it's irresponsible," said Gemma Oaten, manager of eating disorder charity Seed. She called for the app to be banned.
"These apps, and the platforms they are put on, have a duty of care - especially during a pandemic when eating disorders have skyrocketed.
"We are fighting to save lives. This just undermines it all."
Carrot Fit was featured by Apple as part of a short list of recommended fitness apps which appeared at the top of the App Store. It is not available on Android's Play Store.