February 1939 magazine advertisement. Ironized Yeast, the quick way to gain weight so you’ll look better in a bathing suit.
Don’t be scorned, get more dates, thicken up.
Oh how things change. Cheap, abundant trash food, and no physical labor.
Pack it on!
Preindustrial Craftsmanship 
I think adding weight via ironized yeast during the depression era was very popular. I guess it made you look well fed, ergo well-to-do, and therefore “appealing.” I wonder if its somehow just the opposite today.
I think that it’s always been the wealthy that are fatter and better fed. It’s all turned around now with cheap food and low-labor work. I just thought the add was amusing.