Nos homens é uma suspeita, nos ratos foi confirmado (e devido a uma alimentação baseada apenas em milho por falta de mais diversidade em França):
https://www.theguardian.com/world/2017/jan/28/frances-wild-hamsters-being-turned-into-crazed-cannibals-by-diet-of-corn#img-1
Citando:
"The monotonous diet is leaving the animals starving, scientists discovered almost by accident. The problem is a lack of vitamins. In fact, one in particular: B3, or niacin.
Researchers led by Mathilde Tissier at the University of Strasbourg had set out to determine whether hamster diet affects their ability to reproduce in the wild.
Earlier work had looked at the impact of pesticides and mechanised ploughing, which can destroy their underground homes, especially during hibernation in winter. But the possible link with what they eat remained unexplored."
(...)
"In a second set of experiments, they offered hamsters corn-based diets, one of them with B3 added. Sure enough, the vitamin-enriched diet was enough to eliminate the horrific symptoms, and prevent the female hamsters from eating their young.
The dire consequences of the B3-deficient corn diet, the scientists concluded, stemmed not from reduced maternal hormones, but rather a change in the nervous system that induced the same “dementia-like” behaviour diagnosed in humans."
