[pilsetnieks]

No, that's false. It was actually General Foods for Grape Nuts: https://priceonomics.com/how-breakfast-became-a-thing/

[Bartweiss]

I can't speak to the origins, but Kelloggs does use "the best way to start a day" as a slogan, not just to describe their own brands but about cereal in general: https://www.kelloggcompany.com/content/dam/kellogg-company/f...