One of the likely reasons the elderly today are mostly thin is they lived through the depression and know what it's like to go hungry from food shortages. They have a respect for food and gluttony disgusts them even more than most folks here. Also, they learned to eat before our diets changed to an abundance of processed foods, cheap-high fat/lower protein meats and food from a window, in a car. Also, they eat slower and enjoy meals at a table with conversation and complex cooking vs. slurping down food from a bag/microwave as fast as possible in front of a TV ('merica).