Amaranth

What it is and how to eat it

Amaranth is the tiny seed of several Amaranthus species, cooked like a grain although it is not one, and a 2023 article in the International Journal of Molecular Sciences explains that it was domesticated twice, in Mexico and in Peru, where Peruvian amaranth (Amaranthus caudatus) is called kiwicha. In Mexico, the Diccionario de americanismos calls the plant and its seed alegría, used in atole, tamales and sweets, and in Mexico and El Salvador the word also names a sweet made with toasted and popped amaranth seeds and piloncillo (unrefined cane sugar) syrup. This page covers uncooked amaranth grain according to USDA, with 371 kcal, 13.6 g of protein, 6.7 g of fiber and 7.61 mg of iron per 100 g.

A 30 g (1.1 oz) serving, weighed uncooked, provides 111 kcal, 4.1 g of protein and 2 g of fiber, and cooked in water USDA gives it 102 kcal and 3.8 g of protein per 100 g, so it works as one more grain and not as the protein part of the plate. The 2025 nutrition advisory on GLP-1 therapy suggests eating protein first, and popped amaranth works sprinkled over a yogurt or in a porridge made with milk, which provide the protein. The same advisory suggests avoiding fatty or high-fiber foods in the first days of treatment, so in those days a tablespoon may be enough, and alegría also contains honey or sugar.

What the evidence says

The comparison with maize is mine: with USDA's figures, uncooked amaranth has 0.747 g of lysine per 100 g, and according to the FAO lysine, an essential amino acid, limits the quality of maize protein together with tryptophan. In a 1989 study in rats, published in Plant Foods for Human Nutrition, the protein of parboiled amaranth did not differ from milk casein in how well it was used, but popping or roasting it with dry heat damaged some of its lysine, and popped amaranth was used less well. A 1990 paper from the Instituto de Investigación Nutricional in Lima notes that, in young children, replacing up to half of the maize protein with toasted amaranth had shown no advantage over maize or amaranth alone and lysine losses from the heat were suspected, but its analysis of blood amino acids pointed to leucine and threonine as the limiting amino acids. With 6.7 g of fiber and 7.61 mg of iron per 100 g it exceeds the EU minimums for "high fibre", 6 g, and "high iron", 4.2 mg, and it could carry the authorized claim "iron contributes to normal oxygen transport in the body" (Regulations (EC) No 1924/2006, (EU) No 1169/2011 and (EU) No 432/2012).

The sources for this section are listed under "Sources" at the end of the page.