A woman cracks the hull of a betel nut with her teeth to get to the meat to chew.

A woman cracks the hull of a betel nut with her teeth to get to the meat to chew.

New research on ancient human remains suggests the habitual usage of betel nuts, a plant seed with mind-affecting properties that is popular in parts of Asia despite the health risks it presents.

(Image credit: Claire Harbage/NPR)