Obesity really took off after the government issued dietary guidelines calling for people to eat more grain and not eat natural fats.  Prior to the 1930s the most common fats consumed were lard and butter.  Starting in the 1930s, cheap substitutes in the form of processed vegetable oils were pushed onto the market.  Do any of you remember what McDonald's fries were cooked in prior to the 1990's?  The fries were cooked in beef fat.  Then the food police got involved and decreed that processed vegetable oils were better for you.  My goodness did they get that wrong.  Once that happened, our nation has never been fatter or sicker.  As for myself, I avoid all vegetable oils.  I have seen what happened to my relatives eating a doctor and government approved no cholesterol diet.  They all ended up crippled or dead before their time.