A woman with a "perfect body" in 1930 would barely get a second look from Hollywood producers or model casting agents today.
Addiction and eating disorder recovery site Rehabs.com worked with digital marketing agency Fractl on a project looking at the origins of Body Mass Index (BMI) measurements, and how the bodies of ideal women have compared to national averages over time. And their findings show that models and movie stars are getting smaller than the average American woman at unprecedented rates.
Though BMI measurements don't distinguish between fat and muscle, and are thus fairly inaccurate in determining whether someone is obese or not, BMI data from the past makes for interesting comparisons. According to the Center for Disease Control, the BMI of the average American women has steadily increased over the past half a century, from 24.9 in 1960 to 26.5 in the present day.
In a similar vein, Rehabs.com found that the difference between models' weights and the weight of the average American woman has grown from 8 percent in 1975 to over 23 percent today. The bottom line? There's more of a noticeable gap between the bodies of idealized women and everyday people.
Picking up on this disparity, brands like Dove, Debenham's and H&M have made efforts to include diverse body types in their catalogs and ads. Organizations like The Representation Project are working to educate women and girls about media literacy and how to handle the sexualized images of women we see on television, billboards and the Internet. (Of course, we still have a very long way to go.)
In addition to the work of brands and organizations, looking back on the "ideal" women throughout the past century tells us just how arbitrary any vision of "the perfect body" is. Sex symbols have varied in terms of body shape, height, weight and tone, from the hourglass figure of Mae West to the waif-like Kate Moss. Though the diversity of these icons is limited -- they are all white, and none could be accurately described as plus-size -- it's gratifying to see that different body types have been construed as sexy, and likely will be again.
Here's how the "ideal body" has changed in the past 100+ years:

In 1910, he told a reporter for the Sunday Times Magazine:"I'll tell you how I got what you have called the 'Gibson Girl.' I saw her on the streets, I saw her at the theatres, I saw her in the churches. I saw her everywhere and doing everything. I saw her idling on Fifth Avenue and at work behind the counters of the stores."

In 1920, a lecturer named R. Murray-Leslie described flappers as "the social butterfly type… the frivolous, scantily-clad, jazzing flapper, irresponsible and undisciplined, to whom a dance, a new hat, or a man with a car, were of more importance than the fate of nations."

West allegedly once said: “Cultivate your curves -- they may be dangerous but they won't be avoided.”


"The body is meant to be seen, not all covered up," Monroe once said.

Twiggy has spoken out against the thinness ideal while recognizing her own role in perpetuating it.
"I was a very, very skinny model in the 60s, but naturally... that's what I looked like," She told The Huffington Post in 2010. "I ate. I always said I ate, and I looked like my dad who was very skinny, so I think that's genetic... if you are 17 years old and you are 5-foot-11, the chances are you're going to be thin."

The '70s also saw the rise of anorexia nervosa as larger numbers of women strove to be thin. CORRECTION: An earlier version of this story misspelled Farrah Fawcett's name.

Actress Jane Fonda was the face of the fitness craze and the epitome of the "hardbody" -- her aerobic exercise videos sold millions of copies.
The 80s also saw the introduction of supermodels like Naomi Campbell and Claudia Schiffer, whose tall, thin bodies were far from the average American woman's body type.

Moss has famously said, "Nothing tastes as good as skinny feels."

To read more on this topic, check out the full study from Rehabs.com.
CORRECTION: A previous version of this story misidentified a photo of Clara Bow as Mae West. The image has been updated.