How are Hollywood’s hottest stars like Eva Mendes, Jennifer Aniston and Nicole Richie staying so slim? SHAPE magazine has all the details about all the diet plans that the stars can’t live without.

The 5-Factor Diet derives its name from the number of elements each meal should include – protein, complex carbs, fiber, fat and fluids.  Created by celebrity trainer Harley Pasternak, it should come as no surprise that Hollywood starlets such as Eva Mendes, Megan Fox, Katy Perry and Kate Beckinsale all are fans.

Nicole Richie, Rooney Mara and Gwen Stefani have all tried the Pressed Juicery diet, which is a six-juices-a-day, 1,200 calorie intense cleanse.