The beauty ideal has never been as egalitarian as it is today. All it really takes is fitting into a size zero, a severe bronze, Brazilian bend and a cheerleader smile. However, at the same time as asymmetric faces such as Sarah Jessica Parker grace the covers, the expectation on each person to attain such "perfection" as displayed on the cover increases.
You frequently hear that size 0 is a bad ideal because it is unattainable. That is, of course, nonsense. It is attainable, but it costs a lot to attain for most people (mood swings, pain etc) - and therefore, only those most keen to attain it succeed (though, of course, exceptions exist).
The reason why the size 0 ideal is bad is because it is attainable through, for most people, blood, sweat and tears. Beauty is supposed to be something wonderful, diffuse, hard to define yet undeniable, not a objective competition.
There are two main reasons why it is undesirable with a beauty standard of this objective sort. First, of course, that it's not healthy, but in a world swamped by obesity such arguments fall pretty flat. The second argument - when you set up an ideal that is difficult to attain, but within most people's reach, you end up idealizing the people who make the most effort, whose only interest, really, is to be admired and seen. The result is ugly photographs of people with knobbly knees, crossed eyes, asymmetric faces, narrow set eyes etc etc - on covers and magazines. This is what has happened, that is why there are hundreds of magazine covers featuring Renee Zellweger despite the fact that her eyes are half the size of a regular person's and she looks like she just swallowed a lemon.
What is absolutely unattainable to most people, however, is the body structure of Cindy Crawford or the odd sculptural perfection that is Kate Moss. These are people who only need to pull a comb through their hair and get up in the morning in order to look drop dead. It has always been this way, and it will always remain. Life is not fair. If we're going to idealize beauty, why don't we idealize that type of person rather than those who devote their lives trying to look good enough for a cover shoot?
You could argue that because beauty is important and unfairly distributed, why not make it a fair competition - the one who makes the most effort wins? At the end, this depends on what you think is most important.
Is beauty as an aesthetic experience more important than being fair in every respect?