Bilingual children who regularly use their native language at home while growing up in a different country have higher intelligence, a study has found.

Research carried out by the University of Reading in the UK showed that children who spoke one language at school but practiced their native tongue at home with their families scored better in intelligence tests than those who spoke only their non-native language.

The study of 100 Turkish children, aged 7-11, living in the UK used a non-verbal IQ test to compare those who spoke English at school and Turkish at home with those who spoke English at both.

"It is easier to develop concepts at a young age in a first language and then learn a new word for it later in a different language," said Michael Daller, associate professor at the University of Reading in the UK.

"Children who have to learn to understand things for the first time in a less familiar language will find it much harder, so it follows that the children in our study who had done this scored lower on the IQ test," said Daller, who led the study.

"The research suggests parents can help their children develop their intelligence by encouraging them to use their native language at home, as this won't be supported at school," he said.

The researchers say that native languages should be practiced at home through 'meaningful communication'.

This includes reading books and having conversations.

Being bilingual has been shown to have positive effects on the brain, due to the work involved in suppressing one language or the other at all times depending on the situation.

Research has shown this exercising of the brain can even delay the onset of Alzheimer's disease.