"I used to spend four hours a day looking through Instagram and feeling bad about myself," she told BuzzFeed.
"Why's everyone on a beach? What is this stylised courgette rubbish?"
She said people really warmed to it: "They were like, 'Oh, cool, I'm vile 95% of the time too.'"
Pretty soon the account blew up and she was receiving lots of compliments in her inbox.
The only time she got some nasty comments, she said, was when it got featured on the Daily Mail's website: "They called me an orc on a day trip to Earth!" she laughs.
She did initially worry that the account could be construed as bullying, but as she says, Instagram's "completely saturated" with these accounts, so she's not singling anyone out.
And, she says, "I live with a proper hippy yoga teacher and she loves it!"
Younger said that in real life she's not quite as unhealthy as the account suggests, "though I do eat everything on there".
"Well, I don't drink Blue WKD for breakfast," she added.