They’re traditional sweets, made from popped amaranth seeds, specked with peanuts and raisins, offered in flavors that run from coconut to Neapolitan, choco-mint to strawberry. The alegrías (which means “joy”) catch customers’ eyes with snow-cone-bright colors and cotton candy pastels.

So it’s hard to align this sweet snack with its culinary history, based on an ancient grain believed to have been used in Aztec sacrifices of young virgins. The amaranth was mixed with honey, sculpted into deities and then broken up and received much like Holy Communion, with worshippers eating the “bones’’ and “meat’’ of the gods.

Bet you can’t eat just one.

Santiago Tulyehualco, a rural community outside Mexico City, is famous for its amaranth snacks. Besides the alegrías, there are stacks of hockey-puck-shaped disks called ruedas, crunchy cookies and moist muffins, cartoonishly bright obleas, which look like fluorescent tortillas, and even edible amaranth Virgins of Guadalupe.

“It’s a part of Mexican culture, because the Aztecs ate it, along with beans and corn and chia. It was part of their basic diet,” said Karina Martinez de la Rosa, 35, a third-generation amaranth producer whose chia cookies with amaranth are hot sellers in the bustling Casahuates co-op shop run by her aunt and uncle.

Mexico has assumed the dubious distinction of being one of the fattest countries in the world and the No. 1 per capita consumer of soda, and it isn’t hard to see why. Coca-Cola and Cheetos have penetrated every corner of the country, from Tijuana to Chiapas, where vendors hawking Mexico’s famous vitamin T (tacos, tortas and tamales) and convenience stores stocked with comida chatarra (junk food) are seemingly infinite and omnipresent.

In the face of a global nutrition transition — from traditional-agriculture-based diets to what obesity experts have labeled an obesigenic and toxic environment, the amaranth producers, or amaranteros, of Tulyehualco hold firmly to their community tradition while innovating to meet market demands. Amaranth, they believe, represents an opportunity for Mexicans to recover their traditional diet and reclaim their cultural identity.