The idea of a breakfast flake that would aid digestion supposedly came to Kellogg in a midnight revelation, and he set to work on it the following morning. Post beat him to it, though, with his Grape Nuts, which by 1900 had earned him what was then the single largest, fastest legitimate fortune in America.
Grape nuts takes some getting used to but has sufficient fiber content it certainly aids in digestion. I've done my research on this one.
