The diet of each of 250 mothers was correlated with the IQ of her child. When the IQ was > 90, no systematic relationship was observed. Below an IQ of 70, all mothers consumed a similar diet-one with a smaller amount and variety of fruits and vegetables, but larger amounts of yams, greens, corn, rice and dry legumes. This diet was uniquely deficient in none of the common nutrients. The correlation with diet could be due to the presence of a toxicant, such as aflatoxin.