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SAHMRI Women and Kids
22 March, 2017

Taking fish oil tablets doesn't make kids smarter, SA study reveals

SAHMRI Women and Kids

Taking fish oil supplements during pregnancy won’t make your children any smarter, new research reveals.

While expecting mums worldwide have long forked out for fish oil, sold and advertised by supplement brands as promising to help brain and eye development of children, a study by South Australian Health and Medical Research Institute scientists has shot down the claims.

A study of more than 2500 women, released today, found taking a daily 800mg dose of docosahexaenoic acid (DHA) — an omega 3 fatty acid found in fish oil — does not lead to children with higher IQs.

In fact, taking the supplement, made no improvement in a child’s general intelligence, language and motor development at 18 months old or at age seven.

Lead author Dr Jacqueline Gould said the researchers started the 10-year study to determine whether taking DHA had any effect on a child’s brain function, development and eyesight.

“Half the women were given a placebo (vegetable oil) tablet and half were given the DHA, fish oil supplement,” she said.

When the children reached 18 months old, the mums who took the fish oil supplement had noticed no change in their child’s development.

“We wanted to keep track of children as they kept getting older (because) the brain keeps developing through childhood,” Dr Gould said. Then, at age seven, 543 children participated in a follow-up study.

Dr Gould said the researchers found “there was no effect on IQ” and “no effect on their eyes” for children of the mums who took the supplement. “Taking (fish oil tablets) didn’t have any benefit but didn’t cause any harm,” she said.

Dr Gould said she was surprised by the findings.

“When I first started in this field, I really did think fish oil had a benefit (and) it would have been lovely to have a positive effect,” she said. “A lot of what the public knows about fish oil has come from the supplement manufacturers and promoted by them.”

Now, the SAHMRI scientists are hoping to determine whether DHA has an effect on preventing preterm birth.

“We found (10 years ago) women who had the fish oil had slightly longer pregnancies and this lowered the number of children born preterm just slightly,” Dr Gould said.

“If it works, fish oil would be the only intervention we can do to prevent the general population of having a preterm (birth).”

Kate Menhennett, 33, of Lockleys, is 29 weeks pregnant with her second child and said she takes fish oil regularly.

“Last pregnancy I was very religious with (taking) fish oil,” she said.

Despite the findings, the naturopath said she would continue taking the supplement.

“Maybe (the DHA) is not passing the placenta (to the foetus) as much as we thought,” she said.


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