Amaranth has been cultivated as a grain for 8,000 years. Amaranth is classified as a pseudeocereal; it is grown for its edible starchy seeds like cereals, but it is not from the same family as cereals such as wheat and rice.
The yield of grain amaranth is comparable to rice or maize. It was a staple food of the Aztecs and an integral part of Aztec religious ceremonies. The cultivation of amaranth was banned by the conquistadores upon their conquest of the Aztec nation. However, the plant has grown as a weed since then, so its genetic base has been largely maintained. Research on grain amaranth began in the United States in the 1970s. By the end of the 1970s, a few thousand acres were being cultivated. Much of the grain currently grown is sold in health food shops.
Grain amaranth is also grown as a food crop in limited amounts in Mexico, where it is used to make a candy called alegría (Spanish for joy) at festival times. Amaranth species that are still used as a grain are Amaranthus caudatus L., Amaranthus cruentus L., and Amaranthus hypochondriacus L. The grain is popped and mixed with honey.
Amaranth grain can also be used to extract amaranth oil – a pressed seed oil with commercial uses.