Who are they kidding? Most models and celebs have a way less than healthy lifestyle. They either exist/starve on cigarettes and coffee, do drugs like cocaine to supress appetite, or binge on whatever and throw it all up. The few ones that do have a healthy diet also exercise religiously (like way more than the average person with a regular job could do). There are a few genetically lucky people who can just eat regular food and stay super-slim, but for most people it comes unnaturally or at a great sacrifice.