Aztec Cannibalism and Maize Consumption: The Serotonin Deficiency Link
Michele Ernandes, Rita Cedrini and Marco Giammanco
In 1977 Michael Harner suggested that the Aztecs might have practiced cannibalism to obtain animal proteins. A year later, Bernard R. Ortiz de Montellano objected that the Aztecs could obtain all the required aminoacids from vegetable sources, and that their cannibalism was simply a thanksgiving ritual, because its occurrence generally coincided the maize harvest. But at about the same time other researchers showed that maize consumption could provoke brain serotonin deficiency, which, in turn, could provoke some neurobehavioral after-effects, such as the tendency towards aggressive behavior or religious/ideological fanaticism. In this study we attempt to show that a maize diet may cause serotonin deficiency and that this could explain cannibalism and other peculiarities of Aztec culture. The conclusions reached in this study are consistent with past and recent evidence of cannibalism among the Anasazi, a people that was similarly heavily dependent on maize for their nourishment. More broadly, our findings indicate a probable alimentary background for aggressive or fanatical behavior in populations heavily dependent on foods that can lower brain serotonin.