Three grasses, rice, maize and wheat, supply two-thirds of what humanity eats
For all the world's cuisines, most people live on a surprisingly short menu. Just 15 crops provide about 90 percent of the food energy people get from plants, and rice, maize and wheat are staples for roughly 80 percent of the world. Rice alone feeds almost half of humanity.
A staple is whatever a population eats so often and in such bulk that it supplies most of its energy, sometimes at every meal. Staples tend to be cheap, easy to get and rich in at least some of the nutrients the body needs. Cereals, legumes and tubers such as potato, taro and yam together account for about 90 percent of the calories humans consume.
Early farming societies prized these crops for a practical reason: they keep. Grain and dried beans could be stored through dry seasons or hard winters, when nothing fresh was available. Rice is usually cooked as whole grains, but most other cereals are ground into flour or meal for bread, noodles or porridge such as mealie pap, while roots can be pounded into dishes like poi and fufu.
Geography decides what fills the bowl. Across Africa, cereals supply an average 46 percent of dietary energy, with roots and tubers adding 20 percent and meat, milk and eggs just 7. Western Europeans get 33 percent from animal foods, ahead of cereals at 26. Roots and tubers matter to more than a billion people in developing countries, and cassava alone is a basic food for around 500 million. Where land is too dry, cold or steep to farm, animals turn inedible vegetation into meat and milk: sheep in Mongolia, bison once herded by the Sioux on the prairies, reindeer tended by the Sami in the Arctic. Some staples have faded, such as quinoa in the Andes, and pemmican, made from dried meat and fat, sustained the Plains Indians.
A single staple cannot cover every need. Diets built almost entirely on maize are linked to pellagra, and beriberi to refined white rice. One author has also argued that rising carbon dioxide levels can lower the nutritional value of some staple crops. As economies grow and trade opens up, many countries have drifted toward more nutrient-dense staples and more meat.
Source: Staple food
