The word fat has fallen out of usage. Some might speculate because of the rampant spread of unhealthy weight gain across the midsection of the populace of developed nations. Here in the good ole USA the word fat is slang in hip hop circles for nice, great or fabulous. The term "living large" is also associated with this word. An older slang reference that paints a similar image is "fat cat". These references have always arisen due to a lack of basic necessities among the working class and a need to picture what a life of abundance would bring. After all more money plus more goods plus more food equals fat right?
But notice today the lack of usage of such words and terms that equate opulence with obesity. Notice that the working class today seems mysteriously silent in this regard. Today's working class is strangely dissimilar to those of previous generations. This is because low cost goods from countries that can import their goods at little expense have created the illusion of excess among today's working class. I say illusion because today people are able to purchase larger quantities but less quality. Very few of what is purchased for or paid for today can be classified as fine or heirloom quality. What we have is cheaply manufactured or form pressed plastic similitudes of actual hand or machine crafted goods. The same holds true for what people are encouraged to ingest and eventually do. Technology and science has made it possible for the large scale manufacture of flavorful, high calorie, low quality edibles.
What has happened for all intent and purpose in our world economy is the exchange of a market economy for a class or caste system, where the wealth is not circulated based upon the quality of craftsmanship or production but by the control of production by the supply of cheap similitudes of the real thing. A high end set of tiffany china is replaced by plastic disposable table ware or a quality cut of farm raised grass fed beef replaced by factory produced hormone injected hamburger. So while the idea of becoming fat has never been an actual ideal but much more of an allegory to an unattainable over indulgence of the working class it has now become the taboo term for an economic class or caste of people who are no seemingly forever separated from a lifestyle that their grandparents daily strived for. So will the real fatso please stand up!