Deakin University researcher Associate Professor Felice Jacka says there is a clear relationship between a pregnant mother’s diet and her child’s mental health.
Associate Professor Jacka, who has been undertaking her research with Norwegian collaborators, says a child's diet in the first years is also a factor.
The study is the first indicating diet is important for mental health in children.
More than 23,000 Norwegian mothers and children were involved in the study, the results of which have been published in the Journal of the American Academy of Child and Adolescent Psychiatry.
The researchers also looked at the children's symptoms of depression, anxiety, conduct disorder and attention-deficit hyperactivity disorder at 18 months, three years and five years as reported by parents.
They found that mothers who eat poorly are more likely to have children with behavioural problems.
Depression and anxiety is also a factor of poor diet.
She recently helped establish The International Society for Nutritional Psychiatry Research.