W. K. Kellogg had worked for his brother in a variety of capacities at the B.C. Sanitarium. Tired of living in his brother's shadow, he struck out on his own, going to the boom-towns surrounding the oilfields in Oklahoma as a broom salesman. Having failed, he returned to work as an assistant to his brother (John Harvey). While working at the sanitariums' laboratory, W.K. spilled liquefied cornmeal on a heating device that cooked the product and rendered it to flakes. He tasted the flakes and added milk to them. He was able to get his brother to allow him to give some of the product to some of the patients at the sanitarium, and the patients' demand for the product exceeded his expectations to the point that W.K made the decision to leave the sanitarium. Along with some investors, he built a factory to satisfy the demand for his "corn flakes".

Inspired by Kellogg's innovation, C. W. Post invented Grape-Nuts and founded his own cereal company in the town. Battle Creek has been nicknamed "the Cereal City."