Asteroids range in size from Ceres-the largest at about 950 kilometers (590 miles) in diameter and also identified as a dwarf planet-to bodies that are less than 1 kilometer (0.6 mile) across. The total mass of all the asteroids combined is less than that of Earth's Moon.
Only about one-third of the protein eaten around the world comes from animals raised for food. Much of the protein consumed around the world comes from vegetarian sources, including grains, legumes, nuts and seeds. Three grains -- wheat, maize and rice -- provide 60 percent of the world's energy, as well as a good percentage of the protein consumed.
As the primary source of energy for the body, carbohydrates play a role in regulating fat and protein metabolism. With a sufficient supply of carbohydrates to meet the general needs of the body, it will not have to use protein and fat for energy. Protein will serve its primary purposes of tissue growth and repair.