The Advantages of Thinness
Darwinian forces are multiple and sometimes contradictory. In a context where only a king can control enough food resources and labor supply to eat enough and do no physical labor so that he becomes fat prestige is conferred by signs of abundance. When junk food is cheap and poor women are fat, then it’s in to be thin.
Obesity researcher Jeffrey Sobal and Albert Stunkard reviewed 144 studies of the relation between socioeconomic status and weight. They found a strong inverse correlation between a woman’s weight and her social and economic status (the higher the status, the lower the weight) in Belgium, Britain, Canada, Czechoslovakia, Germany, Holland, Israel, New Zealand, Norway, Sweden, and the United States and virtually all developed countries. They found a relation every bit as strong in the opposite direction in developing countries with food scarcities. There the higher-status men and women were heavier. In the developed countries, the relation between status and weight was less consistent for men.
The thin ideal is maintained by the high in status through diet and exercise. It is also maintained by social mobility — thin women are more likely to “marry up,” to marry men who have higher social and economic status than their family of origin. Studies in the United States, Germany, Britain all find that upwardly mobile women are much thinner than their counterparts who marry men of the same social class or lower. There is also a genetic component. When identical twins overeat, they gain almost identical amounts of weight and tend to store it in the same regions.