Researchers at Bristol University in the UK say a bad diet could be harmful to a child's IQ.
The study published in the Journal of Epidemiology and Community Health suggested poor nutrition may affect brain development.
It suggests a link between a diet high in processed foods and a slightly lower IQ.
"If children are eating crisps and fizzy drinks and chips and that sort of food, and they're not eating so much of the fresh foods and fruit and vegetables and the fresh fruits and vegetables have lots more vitamins and minerals in them. A brain needs vitamins and minerals to develop properly," said Dr. Pauline Emmett, the study's author.
For the study, the eating habits of almost four-thousand children were recorded at the ages of three, four, seven and eight and a half.
The children then all took IQ tests when they were eight and half.
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