That is quite possibly the teeniest-tiniest waist we have ever seen in the history of waists.
Now, we know Katie isn't our usual type of celeb, but that tum is so teeny we reckon it warrants a mention.
Related article: [Cheryl Cole admits she doesn't watch The X Factor]
Related article: [X Factor Final 12 in lookalikes]
Y'see, Katie has moved to LA so has adopted a new super healthy lifestyle acquiring a stupidly flat tum as a result.
But who also goes to LA all the time? Well, Katie's old X Factor mentor Cheryl Cole, of course!
Katie and Cheryl on the show. Copyright: [rex]
So they must meet up all the time, right?
Well, er, not exactly.
Let's just say Katie and Chezza aren't exactly the best of friends since Cheryl confessed that she only picked Katie after being told by Simon Cowell that she would 'make good tv'.
Katie was not impressed by this and tweeted Cheryl to let her know just how she was feeling.
Katie tweeted: "@cherylcole I thought you were better than this. Shame I trusted you. you live and you learn."
So we assume they won't be going out for a macrobiotic shake anytime soon then?
Katie was picked alongside Rebecca Ferguson and Cher Lloyd. Copyright: [itv]
However, it seems that Katie is still keen to stay in touch with her fellow contestant Cherl Lloyd, writing her a message on Sunday, saying:
"@CherLloyd girl if ur in la hit me up!!! We need a reunion holla for a dollar!!!' (sic)"
Cher is yet to reply but we are totes sure she will 'hit up' Katie soon...