Will Keith Kellogg was an American industrialist in food manufacturing, who founded the Kellogg Company, which produces a wide variety of popular breakfast cereals. He was a member of the Seventh-day Adventist Church and practiced vegetarianism as a dietary principle taught by his church. He also founded the Kellogg Arabian Ranch, which breeds Arabian horses. Kellogg was a philanthropist and started the Kellogg Foundation in 1934 with a $66-million donation.

John Harvey Kellogg was an American businessman, inventor, physician, and advocate of the Progressive Movement. He was the director of the Battle Creek Sanitarium in Battle Creek, Michigan, founded by members of the Seventh-day Adventist Church. It combined aspects of a European spa, a hydrotherapy institution, a hospital and high-class hotel. Kellogg treated the rich and famous, as well as the poor who could not afford other hospitals. According to Encyclopædia Britannica, his "development of dry breakfast cereals was largely responsible for the creation of the flaked-cereal industry."