Supplementing children’s diets with fish oil, enrolling them in quality preschool, and parents engaging kids in interactive reading are effective ways to raise a young child’s intelligence, according to a new study.

Using a technique called meta-analysis, a team led by John Protzko from the New York University Steinhardt School of Culture, Education, and Human Development, combined the findings from existing studies to evaluate the overall effectiveness of each type of intervention.

The results of the meta-analyses indicated that certain dietary and environmental interventions can be effective in raising children’s Intelligence Quotient (IQ).

Supplementing pregnant women and newborns with long-chain polyunsaturated fatty acids, foods rich in Omega-3, were found to boost children’s IQ by more than 3.5 points.

These essential fatty acids may help raise intelligence by providing the building blocks for nerve cell development that the body cannot produce on its own.

There is insufficient research, however, to determine whether other types of supplements – including iron, B-complex vitamins, riboflavin, thiamine, niacin, and zinc have beneficial effects on intelligence, the study found.

In collaboration with NYU Steinhardt professors Joshua Aronson and Clancy Blair, leaders in the field of intelligence, Protzko analysed the best available studies involving samples of children from birth and kindergarten.

Interventions focused on interactive reading – teaching parents how to engage their children while reading with them – were found to raise children’s IQ by over 6 points.

These interventions do not seem to have an effect for children over 4 years old, suggesting that the interventions may accelerate language development, which, in turn, boosts IQ.

Sending a child to preschool was found to raise his or her IQ by more than four points, and preschools that include a language development component were found to boost IQ by more than seven points.

The link between preschool and intelligence could be a function of increased exposure to language or the result of the overall cognitive complexity of the preschool environment.

“Our current findings strengthen earlier conclusions that complex environments build intelligence, but do cast doubt on others, including evidence that earlier interventions are always most effective,” Protzko explained.

“Overall, identifying the link between essential fatty acids and intelligence gives rise to tantalising new questions for future research and we look forward to exploring this finding,” Protzko said in a statement.

The study was published in journal Perspectives on Psychological Science.

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