High fish consumption in pregnancy linked to brain benefits for child

According to a study in Spain, when mothers eat three sizable servings of fish each week during pregnancy it may benefit children's brains for years to come.

Researchers followed nearly 2,000 mother-child pairs from the first trimester of pregnancy through the child's fifth birthday, and found improved brain function in kids whose mothers ate the most fish while pregnant, compared to children of mothers who ate the least.

Even when women averaged 600 grams, or 21 ounces, of fish weekly during pregnancy, there was no sign that mercury or other pollutants associated with fish were having a negative effect that offset the apparent benefits.

MERCURY

"Seafood is known to be an important source of essential nutrients for brain development, but at the same time accumulates mercury from the environment, which is known to be neurotoxic," lead author Jordi Julvez, of the Center for Research in Environmental Epidemiology in Barcelona, said.

In an attempt to balance the potential harms of such pollutants with the general health benefits of fish, the US Food and Drug Administration's 2014 guidelines encourage pregnant women to eat fish, but no more than 12 ounces per week.

WEEKLY INTAKE

The European Food Safety Authority recently issued a scientific opinion endorsing 150 grams to 600 grams of fish weekly during pregnancy, Julvez and colleagues note in the American Journal of Epidemiology. But, the study team wrote, the effects of maternal fish consumption during development are still not well understood and more research could help give pregnant women clearer guidance.

The researchers analysed data from the Spanish Childhood and Environment Project, a large population study that recruited women in their first trimester of pregnancy, in four provinces of Spain, from 2004 to 2008.