Surprise! Models and actresses are skinnier than the general public. But how skinny and how do their body shapes change throughout history?

Diet Blog has the timeline:

The 1920s and 1960s both bucked the trend of the curvaceous woman. Ann Bolin, an anthropologist at Elon College suggests that “during periods of liberation, like the 1920s, when women had just gotten the vote, and the 1960s, when the Pill became available, the ideal shape for women deemphasized their reproductive characteristics–the nourishing breasts, the wide, childbearing hips.”

Other measures of physical beauty show a very clear trend towards slimness.

* Waist measurements of winners of the Miss America pageant went from just under 26 inches (1920) to around 24 inches (1980s).

* During the period from 1979 to 1988, 69% of Playboy models and 60% of Miss America contestants weighed 15% or more below the expected weight for their age and height category.