In fact, the 23-year-old is gearing up for her wedding to rapper Professor Green next month and has been on a healthy exercise and diet regime to get herself into shape for the big day.
Writing in her new lifestyle blog, the model and make-up artist explained that her slender physique is in part down to good family genes - with a sensible attitude to healthy food thrown in.
“I always start the day with a smoothie,” she said.
“I was brought up always being told everything in moderation; a saying that really is the most effective diet - even though it sounds so simple!”
She admitted that she’s got a “massive” sweet tooth and that her favourite meal is spaghetti, so although she’d rather be avoiding the gym she’s come to see it as a necessary evil if she wants to go on enjoying her food.
Millie’s got a few tricks up her sleeve when it comes to looking and feeling good, and notes that there’s no point starting up a gruelling exercise routine if you’re not watching what you eat. “If you want to tone up the first thing to look at is your diet. There is no point going to the gym if you aren’t giving your body the right fuel,” she wrote.
Millie’s super-healthy day in food