Chia seeds are the edible seeds of Salvia hispanica, a flowering plant in the mint family (Lamiaceae) native to central and southern Mexico, or of the related Salvia columbariae of the southwestern United States and Mexico. Chia seeds are oval and gray with black and white spots, having a diameter around 2 millimetres. The seeds are hygroscopic, absorbing up to 12 times their weight in liquid when soaked and developing a mucilaginous coating that gives chia-based foods and beverages a distinctive gel texture. There is evidence that the crop was widely cultivated by the Aztecs in pre-Columbian times and was a staple food for Mesoamerican cultures.Chia seeds are cultivated on a small scale in their ancestral homeland of central Mexico and Guatemala and commercially throughout Central and South America.