The 27-year-old singer-turned X-Factor judge said that she doesn't mind suffering in high heels as long as her comfy slippers are nearby.
She told InStyle magazine, 'I adore Charlotte Olympia shoes. The heel is so high, but you have to suffer for your art. They're sitting-down shoes.
'I love how lots of girls swap flats for heels when they get to work.
'I've just discovered a lot of them carry fold-up ballet pumps. I usually put my big fluffy slippers in my car to change into after an event. But I'd look much cooler in those ballet shoes.'