The graham cracker was originally conceived of as a health food as part of the Graham Diet, a regimen to suppress what Reverend Graham considered unhealthy carnal urges, the source of many maladies according to Graham. Reverend Graham would often lecture on "self-abuse", as masturbation was commonly called at the time. Graham would often say how these experiences were inspired by children eating crackers. One of his many theories was that one could curb one's sexual appetite by eating bland foods. Another man who held this belief was John Harvey Kellogg, the inventor of the corn flakes cereal.
Most modern graham crackers are made mainly of the refined white flour to which the Rev. Graham was opposed, and others are made with blends that use white flour as a base. Graham crackers have remained popular in North America as a snack food despite, or perhaps because of, greater amounts of refined sugar (often mixed with honey) and less graham flour than the original versions, which may have been unsweetened.
Some modern, commercial graham crackers could no longer be considered a health food. In fact, some of these commercial "graham crackers" are more notable for being topped with a thick crust of cinnamon and sugar or having chocolate flavoring or coatings added. Technically, crackers are not really graham crackers unless they are made with graham flour, which is a hard (high protein) wheat flour in which the constituent bran, germ, and endosperm have been ground separately, the first two coarsely and the third finely.
Basic modern graham crackers are common in America as a snack for young children, at home or at preschool, early elementary school, and other child care facilities.
Graham crackers, along with marshmallows (roasted or unroasted) and milk chocolate bars, are used to make a simple dessert or treat that has come to be called "s'mores" (a contraction of the end of the phrase "give me some more") in North America.