But does that stop this supermodel from tucking into a huge plate of steak and chips before a show? No way!
Alessandra, 32, happily munched a giant cut of steak, complete with fries and a bearnaise sauce, on Sunday - just THREE days before she was due to strip down to her smalls for a Victoria's Secret show.
The model and mum of two posted a snap of her delicious looking meal on Instagram, saying: "#sundayfunday #pastis #steaknfries."
She was dining at New York restaurant Pastis, and looked lovely and laid back in a pair of purple sunnies.
On Wednesday, Alessandra will do what she does best and don an array of beautiful outfits for the latest VS show.
But it's not all greasy food and lounging around, as Alessandra's been working out to get herself in shape for the catwalk, too.
She's uploaded snaps of herself doing yoga and circuit training, as well as doing a barre workout, which is said to help sculpt legs and bum.
We wish we looked this good after eating our body weight in chips!
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