breakfast cereal, a food made from grain, commonly eaten in the morning. The oldest type of cereal, known as porridge or gruel, requires cooking in water or milk. The modern breakfast cereals, however, are entirely precooked and eaten in cold milk. The first precooked cereal was probably invented in 1863 by James Jackson. He broke up hardened loaves of unleavened whole grain bread into little pieces and served it for breakfast after soaking the brittle chunks overnight in milk. Jackson named this mixture granula. In 1877, Dr. John Harvey Kellogg created a similar cereal called granola, but not until his invention of corn flakes in 1902 did cereal become a commercial success. At first, most cereals were marketed as pure, whole-grain foods. Eventually, however, competition resulted in the addition of sugar and other food additives and in marketing campaigns directed at children, such as the inclusion of a premium or toy in the box. In the 1970s, as cereals came under attack for their lack of nutritive value, many manufacturers began adding nutrients. Unlike most other grain products, breakfast cereals have shown a steady increase in per capita consumption in the United States throughout the 20th cent. Apart from breads, cereal is the most common form in which Americans consume grain.