Celebrity diets: the good, the bad and the ugly.

Just how do the A-list keep their figures so darn perfect all the time, while the rest of us can only dream of squeezing ourselves into a size 8? A good plastic surgeon can go a long way, but extreme dieting is the secret to many a slyph-like figure we see gracing the red carpet. Some stars are prepared to go to extraordinary lengths to stay slim, undertaking diets that go from weird to downright dangerous.

We take a look at how Gwyneth Paltrow, Kirsten Dunst, Jennifer Aniston, Beyoncé & Co stay trim, and ask our dietician what she thinks of their choices. Prepare to be shocked...