For most of my life, I've assumed that the grotesque amounts of coffee I began drinking around age 12 to keep up with my nightly homework load had something to do with the fact that I grew up to be a good 2-to-3 inches shorter than my pediatrician predicted. Coffee, as we've all heard, is supposed to stunt a child's growth. And I guzzled it from my tweenhood on.

It seems, though, that I assumed wrong. As Smithsonian's Joseph Stromberg recently explained in great piece of pseudoscience debunkery, the idea that coffee is bad for youngsters was actually a myth first propagated by the early 20th century cereal Tycoon, C.W. Post.

Before he developed his signature breakfast products like Grape Nuts, Post went into business in 1895 selling a cereal-based, caffeine-free coffee substitute called Postum. Now, the words "cereal-based, caffeine-free coffee substitute" might sound about as appetizing to you as a wet wad of newspaper. But Post cannily marketed his product as a health beverage while spooking consumers about the allegedly malign effects of coffee on both adults and children.

Here is how one seemingly skeptical journalist explained the product's success in a 1922 issue of the Magazine of Wall Street:

Not himself a chemist, or a psychologist, or whatever one must be to establish that coffee drinking is harmful, the writer claims no knowledge of whether “Postum Cereal,” as it was called, met a real need, or merely played on a superstition. At any rate, the product proved to have a market. And backed by unceasing, driving efforts on the part of Mr. Post himself, that market was nurtured and developed until it became nation-wide.

This 1933 ad, turned up by Stromberg, claimed that "by crowding milk out of the diet of children, coffee is a cause of undernourishment. It robs children of their rosy cheek sand sparkling eyes. It lowers their vitality, lessens their resistance to disease, and hampers proper development and growth." It also declared that a "world famous Research Institute" had found conclusive evidence that drinking coffee brought down children's grades.

Image via wjm2234.com and Surprising Science

"Children 'brought up' on Postum are free from the evil effects of caffeine—the habit-forming drug—in coffee and tea," a 1910 ad informed parents, beginning a pitch that would probably go over fairly well with many a Whole Foods shopper today.