Amaranth has been cultivated as a grain for 8,000 years.  The yield of grain amaranth is comparable to rice or maize. It was a staple food of the Aztecs, and was used as an integral part of Aztec religious ceremonies. Its cultivation was banned by the conquistadores in 1516. Because the plant has continued to grow as a weed since that time, its genetic base has been largely maintained. Research on grain amaranth began in the US 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: "happiness") at festival times. The grains are popped, and mixed with honey.
As the following table shows, grain amaranth is particularly nutritious.
|Total carbohydrates||63.0 g|
|Ascorbic acid (Vitamin C)||3.0 mg|
|Thiamin (Vitamin B1)||0.14 mg|
Notable nutritional attributes of amaranth grain include:-
- The protein, which is of an unusually high quality, according to ECHO.
- A ¼ cup of amaranth grain supplies 60% of the Recommended Dietary Allowance of iron. 
- Amaranth grain is free of gluten, which is important for people with gluten allergies.
- ↑ 1.0 1.1 G. Kelly O'Brien and Martin L. Price (1983). "Amaranth: Grain & Vegetable Types". ECHO Technical Note.
- ↑ Thomas Jefferson Agricultural Institute. "Grain Amaranth: A Lost Crop of the Incas". (PDF version also available)
- ↑ J.N. Cole (1979). Amaranth: from the Past, for the Future. Rodale Press, Emmaus, PA.
- ↑ "Certified Organic Amaranth Typical Quality Analysis". American Health & Nutrition.