The 'Ideal' Female Body Size, Over Time
Female attractiveness is nebulous and varies over time and place. Both field and lab-based research have focused on quantifying female attractiveness and much of this research suggests that waist-to-hip ratio (WHR) is a reliable measure of female attractiveness. Dixson and coworkers have shown, via multiple studies, that the ideal WHR varies spatially. In the United States, China and New Zealand, the ideal WHR is 0.6, while indigenous peoples in Papua New Guinea prefer a larger figure, a WHR of 0.7. The average American WHR is 0.8 much greater than the average ideal WHR. Not surprisingly, research shows that the average American male will more frequently select females with average to lower WHRs, but not higher than average WHRs.
One might argue that the ideal American female form is typified by the body types seen in print or film. Perhaps the most famous print periodical is Playboy Magazine. Playboy Magazine published their first nude editorial in December of 1953. Over the more than six decades of published nudes, the body measurements have shifted. Over time, the body mass index of the models have consistently decreased while the waist-to-hip ratio has steadily increased. To visualize this trend imagine thinner, less curvy women.
Waist-to-Hip Ratios Are Steadily Increasing
Although the 1950s women had higher BMIs, the Playboy models of the 2000s have 9.1% larger waist-to-hip ratios than the Playboy models of the 1950s. Waist-to-hip ratio is a ratio of the circumference of the waist to the circumference of the hips and is widely researched as a measure of female attractiveness. Much research has been done to identify an 'ideal' wand
After a Steady Decline, Body Mass Index Has Recently Increased
Body Mass Index is a weight-to-height ratio and is generally used as a measure of tissue proportions, where a BMI of 18.5-25 is generally regarded as normal weight. As a reference, published BMI images can be viewed here. As can be seen in the above figure, many models have BMI values less than 18.5, which are regarded as 'underweight'. Compared to the women from the 2000s, the 1950s women were larger with 5.7% higher body mass indices. BMI was highest in the 1950s which means these models were the largest. Interestingly, we see an uptick in BMI since a low in the mid 1980s.
No Change in Cup Size
Cup size refers to the volume of the breast where A is the smallest and F is the largest cup size. The cup size data show few trends over time. Perhaps the most significant finding is that 'C' cups are the most common.
If we accept that Playboy models typify the contemporary and ideal female form, then we see that preferences change. Since the 1950s, we see that men have gradually preferred less curvy woman, i.e., larger WHR. We also see that cup size preference is relatively stagnant. Lastly, we see that BMI preferences have changed the most and are near the lower end of 'healthy' weight.