Los Angeles - Rihanna is unhappy with her size zero figure.
The Where Have You Been singer has admitted to being a tiny UK size four but would prefer her fuller figure back.
She told Us Weekly: "I'm a size 0 - and not happy about it! I went way too far. I prefer myself a bit chunkier. I want my old butt back!"
The 24-year-old is working on her seventh CD and is trying to squeeze in some more relaxation time.
But her jam-packed calendar is having a slimming effect on her famous beach body.
The Battleship star said: "I want to do two more [movies] before touring again next year. My schedule is crazy!"
The Barbados-born beauty was recently admitted to hospital for fatigue following her appearance at the Met Ball last month.
She stunned audiences in a black, reptile-inspired Tom Ford gown but had fans worried about her shrinking frame.
She confessed: "I got no sleep [beforehand]. It's harsh on your body!"
Experts have suggested that Rihanna may be suffering from narcissistic personality disorder while friends insist she is "feeling lost".