Final answer:
Dr. John Kellogg developed breakfast cereal based on the dietary practices of the Seventh-Day Adventists. This group favored a diet similar to the Graham diet from the 1830s, emphasizing whole grains and moderation, which influenced Kellogg's cereal creation.
Step-by-step explanation:
Dr. John Kellogg developed the breakfast cereal as a result of the dietary practices of the Seventh-Day Adventists. This religious group was one of several that supported aspects of the Graham diet, which focused on wholesome foods and was developed by Sylvester Graham in the 1830s. The diet emphasized the consumption of fruits, vegetables, and whole grains, including graham flour. These dietary preferences influenced the creation of the breakfast cereal that Dr. Kellogg is known for, as well as the graham cracker, another product of Sylvester Graham's dietary movement. Dr. Kellogg's association with the Seventh-Day Adventists is a noteworthy example of how religious practices can influence dietary habits and lead to innovations like the popularization of breakfast cereal.