The folic and fatty acids found in nuts are said to boost brain development in children (stock image)

The folic and fatty acids found in nuts are said to boost brain development in children (stock image). Picture: Getty

The study suggested that around three handfuls of nuts a week – or 90g – was the optimum quantity to consume.

It is said that the folic and fatty acids are to thank for the supposed boost to brain development that comes with nut consumption.

Researchers have claimed that walnuts, almonds, peanuts, pine nuts or hazelnuts are best for the healthy fatty acids they contain.

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The study, conducted by the Barcelona Institute for Global Health, tested 2,200 mother and child pairs. The women completed a questionnaire on eating habits, and the children later took tests on their memory, thinking skills and attention capacity at 18 months and five and eight years.

Study leader Florence Gignac said: “This is the first study to explore the possible benefits of eating nuts during pregnancy for the child’s neuro-development in the long term.

“The brain undergoes a series of complex processes during gestation and this means that maternal nutrition is a determining factor in fetal brain development and can have long-term effects.

“The nuts we took into account in this study were walnuts, almonds, peanuts, pine nuts and hazelnuts.

Peanuts were among the nuts thought to boost an unborn baby's intelligence (stock image)

Peanuts were among the nuts thought to boost an unborn baby’s intelligence (stock image). Picture: Getty

“We think that the beneficial effects observed might be due to the fact that the nuts provided high levels of folic acid and, in particular, essential fatty acids like omega-3 and omega-6.

“These components tend to accumulate in neural tissue, particularly in the frontal areas of the brain, which influence memory and executive functions.”

The findings were published in European Journal of Epidemiology.