Abstract: From the domestication of wild grasses in the Fertile Crescent 10,000 years ago, to the understanding of their fullpotential nutritional value, cereal crops continue to be essential in the advancement of human cultures. Of the twelve mostimportant crops in the world, five are cereals (rice, wheat, corn, barley and sorghum) which alone account for more than half thecalories consumed by the world’s human populations. The scientific community has begun to understand the important role ofcereal foods beyond a source of calories. The importance of a balanced diet, which includes whole cereal grain foods, can’t be overemphasized. Whole grain foods are a source of dietary carbohydrates, micronutrients and phytochemicals. An example would bethe aleurone layer of cereals, which is especially rich in a number of phytosterols, with potent antioxidant properties. Anotherexample is the soluble and insoluble cell wall components in the bran which is an important source of dietary fiber. Supportingscientific evidence of the beneficial effect of high-fiber and whole grain foods in maintaining good health and preventing seriousillness is available in the literature. Dietary factors are thought to affect body weight and the overall state of the body inpreventing illness. The relationships of complex carbohydrates, whole grain products and the prevention of some diseases,including type-2 diabetes mellitus and coronary heart disease are summarized.