Prenatal exposure to fish beneficial to child development: New study adds to evidence that 'good' outweighs the 'bad'

January 4, 2013, University of Rochester Medical Center

Prenatal exposure to fish beneficial to child development, study suggests
Resolution: Eat more fish
(Medical Xpress)—A study published recently in the Journal of Nutrition adds to the growing scientific evidence that when expecting mothers eat fish often, they are giving their future children a boost in brain development even though they are exposing their children to the neurotoxin, methyl mercury, present in fish.

The (FDA) advises pregnant woman to eat only two meals of fish a week and to avoid most large fish to reduce the exposure of their babies' developing brains to mercury. However, a recent joint report from the and the Food and Agriculture Organization of the United Nations recommended nations actually emphasize the benefits of eating fish for pregnant women and nursing mothers and the potential risks of not consuming fish to .

These messages are confusing for consumers, which is why researchers at the University of Rochester, the University of Ulster, and in the Republic of Seychelles are trying to sort out what happens to children's development when their mothers eat fish while pregnant. The study, which was published in November, included 225 mothers and their children, from whom researchers collected detailed information about the of the mothers and completed almost a dozen standard assessments on language and intelligence of the children over several years.

"This study shows that there are no adverse effects of prenatal from fish on children at 5 years old on 10 when adjusted for maternal levels of . In fact, we found positive associations with those nutrients and children's ," said Phil W. Davidson, Ph.D., professor emeritus of Pediatrics, principal investigator of the ongoing Seychelles Child Development Study and an author of the Journal of Nutrition paper.

Women in this new study, which was conducted in the Republic of Seychelles in the Indian Ocean, eat an average of 10 times as much fish as mothers in the U.S. The fish eaten there has about the same level of mercury as fish in the U.S. The study children's standard language development scores rose as levels of omega-3 rose in mothers. These nutrients are important building blocks in the brain and are present in large amounts in fish. Fish are the primary dietary source of many of the fatty acids that play a crucial role in brain development.

"Based on our results, we would argue that the beneficial effects of fish consumption during pregnancy outweigh any adverse effects of methyl mercury," said Sean Strain, Ph.D., lead author of the paper and professor of Nutrition at the University of Ulster in Northern Ireland.

Authors found positive associations between the level of polyunsaturated fatty acids in mothers and their children's subsequent scores on preschool language and verbal assessments. In particular, those scores were associated with DHA, an omega-3 fatty acid.

The Seychelles Child Development Study, headquartered at the University of Rochester, has been studying the impact of maternal fish consumption for three decades and is among the longest running epidemiologic studies. An earlier study showed a positive – and surprising – association between higher levels of mercury in pregnant mothers and subsequent child development. Because mercury is a neurotoxin, the researchers knew that they had to dig further to find another reason. This study points to polyunsaturated fatty acids, but authors say they need to conduct more research to understand the relationship between those fatty acids and methyl mercury in fish.

"The potential interplay of mercury and polyunsaturated fatty acids from appears very complex and we are just beginning to understand their relationship. It may be that polyunsaturated fatty acids impact the inflammation or oxidation that mercury causes in the brain," said Gary Myers, M.D., professor of Neurology, Environmental Medicine and Pediatrics at URMC, child neurologist and a researcher on the Seychelles Child Development Study team.

Explore further: Fish eaters run lower risk of heart attack – despite some mercury content

Related Stories

Fish eaters run lower risk of heart attack – despite some mercury content

September 24, 2012
Eat fish, but avoid fish with the most pollutants. This is the conclusion drawn by a group of researchers at Umeå University in Sweden after having weighed the risks of mercury content against the advantages of healthful ...

Eat fish, build up brainpower

January 10, 2012
Can pregnant women help boost their children's brainpower by eating fish? The findings of a study, presented in the American Journal of Clinical Nutrition, show how children born to women who consumed more fish during their ...

Eating salmon while pregnant affects contents of mother's milk

August 3, 2012
(Medical Xpress) -- Mothers who eat more salmon before giving birth boost levels of a vital nutrient in their breast milk, but could lower levels of disease-fighting antibodies they pass on while feeding their baby, researchers ...

Anthropologists finds high levels of omega-3 fatty acids in breast milk of Amerindian women

June 8, 2012
– Working with researchers at the University of Pittsburgh and the Cincinnati Children's Hospital, anthropologists at UC Santa Barbara have found high levels of beneficial omega-3 fatty acids in the breast milk of economically ...

Recommended for you

Engineered enzyme eliminates nicotine addiction in preclinical tests

October 17, 2018
Oct. 17, 2018—Scientists at Scripps Research have successfully tested a potential new smoking-cessation treatment in rodents.

Self-lubricating latex could boost condom use: study

October 17, 2018
A perpetually unctuous, self-lubricating latex developed by a team of scientists in Boston could boost the use of condoms, they reported Wednesday in the journal Royal Society Open Science.

How healthy will we be in 2040?

October 17, 2018
A new scientific study of forecasts and alternative scenarios for life expectancy and major causes of death in 2040 shows all countries are likely to experience at least a slight increase in lifespans. In contrast, one scenario ...

Study finds evidence of intergenerational transmission of trauma among ex-POWs from the Civil War

October 16, 2018
A trio of researchers affiliated with the National Bureau of Economic Research has found evidence that suggests men who were traumatized while POWs during the U.S. Civil War transmitted that trauma to their offspring—many ...

Father's nicotine use can cause cognitive problems in children and grandchildren

October 16, 2018
A father's exposure to nicotine may cause cognitive deficits in his children and even grandchildren, according to a study in mice publishing on October 16 in the open-access journal PLOS Biology by Pradeep Bhide of Florida ...

Many supplements contain unapproved, dangerous ingredients: study

October 13, 2018
(HealthDay)—U.S. health officials have issued more than 700 warnings during the last decade about the sale of dietary supplements that contain unapproved and potentially dangerous drug ingredients, new research reveals.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.