For years, sorghum was the staple diet in many South African countries and as maize has slowly replaced it, the occurrence of squamous carcinoma of the oesophagus has risen. The reason for this correlation is a specific fungi, fusarium fungi, that grows well on maize, but not well on sorghum. Fusarium fungi reduces nitrates to nitrites and then synthesize cancer-producing nitrosamines.


Isaacon, C. (2005). The change of the staple diet of black South Africans from sorghum to maize is the cause of the epidemic of squamous carcinoma of the oesophagus. Medical Hypotheses, 63(3), 658-660.