We had evolved to adapt to the life of hunters and gatherers and now accepted a life that was incompatible with our adaptive qualities. The consequences were evident in a reduction in body size, from which we have only recently recovered, and in the appearance of diseases of sedentary and agricultural populations, such as cardiovascular disease, cancers, diabetes, high blood pressure, and bone diseases. Many of our current problems can be blamed on our current nutritional and activity differences from our early hunter-gatherer existence. Agriculture may have launched civilizations, with all their advantages, but it also led to disease, wars, and a restructuring of social organizations. This is why Dr. Cordain refers to the development of agriculture as a two-edge sword.
All grains have nutritional deficiencies.
Moreover, as we eat more and more grain products we tend to eliminate other nutritional meats, fruits, and vegetables. In half the world, bread provides more than 50 percent of the total caloric intake, and in a few countries of Southern Asia, Central America and the Far East and Africa cereal products comprise up to 80 percent or more of the total caloric intake. Think about your own intake of grain products. In a month's time, most of us will have eaten several slices of bread, several bowls of cereal with milk, pasta, rice, bagels, rolls, muffins, crackers, cookies, pastries, corn or other forms of chips, and tortillas. Most of these are refined and lack many important nutrients.