Taft was fat, but not obese.
After he left the Presidency a physician ordered him to lose weight or expect to not live much longer. Such indicates pathological obesity. He took the advice seriously.
Obesity was fashionable until about 1910 as a signal of success -- which meant that one was so rich that one never had to miss a meal. After the Progressive Era, in which the words "fat cats" was applied to rapacious Gilded-Age plutocrats, obesity lost its symbolic evidence of success. By the 1930s it became a marker for arrogant, selfish, inconsiderate people other than Santa Claus. Sidney Greenstreet, anyone?
Obesity has slipped socially, devolving to those who overeat as a salve for stresses of life.