Breakfast cereal he launched the Cornflakes brand, which overnight captured a national market. Soon there were forty rival manufacturers in the Battle Creek area. His brother William K. Kellogg (1860–1951) worked for him for many years until, in 1906, he broke away, bought the rights to Cornflakes, and set up the Kellogg Toasted Corn Flake Company. William Kellogg discarded the health food concept, opting for heavy advertising and commercial taste appeal. Later, his signature on every package became the company trademark. The second major innovator in the cereal industry was Charles W. Post, a salesman who was admitted to Kellogg's sanitarium as
John Harvey Kellogg the "Herald" where the book was typeset and ready to print. When it finally appeared in 1903, the book was sharply criticized by White for what she considered its many statements of pantheism. Over the next few years, there was increasing conflict between Kellogg, General Conference President A. G. Daniells and others. In 1907, Kellogg was "disfellowshipped", as part of a schism that split the church. Kellogg retained control of the Battle Creek Sanitarium and the American Medical Missionary College, and continued to promote Adventist ideas of health and well-being at those institutions. In later life, Kellogg spoke positively of