The 32-year-old star revealed she was once told to lose weight by movie bosses but refused to conform to the idea of the perfect Hollywood body.
She said: "When I was shooting a movie once, the faxes went out from the producers and the director to my agents to my manager to call me and ask me to lose weight.
"I just remember sitting in my trailer hysterically crying from the embarrassment I felt about myself, my body - and that no one could talk to me directly.
"I'm an indulger, but then I have to be good. When I'm in really good shape, I like my butt. It's juicy."
However, Ali - who is engaged to actor Hayes MacArthur - admits she sometimes suffers from insecurity as she feels she is constantly judged on her looks.
She added to Allure magazine: "My fiance will always say to me, 'Please - you've got Hot-Girl Syndrome.'
"I think that's where insecurity comes from, because it starts with being celebrated for the way you look... and it's weird that it's something you did nothing to get."
