Source of Nutrients

Most humans derive most of their kilocalories through consumption of cereal grain (or simply cereal), which is a grass that yields grain for food. Grain is the seed from a cereal grass. The three leading cereal grains—wheat, maize (corn in North America), and rice—together account for nearly 90 percent of all grain production and more than 40 percent of all dietary energy consumed worldwide.

Dietary Energy By Source

Wheat, rice, and maize (corn) are the three main sources of kilocalories.

Wheat Farming

Washington State.

Maize Farming

Separating corn from chaff, Gambela, Ethiopia.

Rice Farming

Long An Province, Vietnam.

Protein

Protein is a nutrient needed for growth and maintenance of the human body. Many food sources provide protein of varying quantity and quality. One of the most fundamental differences between developed and developing regions is the primary source of protein. In developed countries, the leading source of protein is meat products, including beef, pork, and poultry . Meat accounts for approximately one-third of all protein intake in developed countries, compared to approximately one-tenth in developing ones . In most developing countries, cereal grains provide the largest share of protein.

Protein By Source

People get most of their protein from meat in developed countries and from cereals in developing countries.

Protein From Meat

The percentage of protein from meat is much higher for people in developed countries than for those in developing countries. Because meat is generally a relatively expensive way to obtain protein, the higher percentage of meat consumption in developed countries is a reflection of higher incomes there.

Cattle Ranch, Colorado

Consuming Sorghum, A Major Source of Protein in Ethiopia

Consuming Sorghum, A Major Source of Protein in Ethiopia

Pause & Reflect 9.1.3

Review the charts below about the protein content of cereal grains and Meat. How do wheat, rice, and maize compare with other grains or with an equivalent serving of meat? Specifically discuss the calorie comparisons between grains and meat.