Recent studies show that consuming high amounts of fish can actually benefit a baby’s brain function. Contrary to the belief that the consumption of large amounts of seafood may contain dangerous levels of mercury, pregnant women who ate on average 21 ounces of fish and other seafood per week during pregnancy saw improved brain function in their children.
Jordi Julvez, lead author of a study done at the Center for Research in Environmental Epidemiology in Barcelona told said in an email that “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.” Therefore, the study recommends that there is no benefit of consuming more than 21 ounces a week.
A separate study at the Tohoku University School of Medicine found similar results in mice, according to the International Federation of Gynecology and Obstetrics. The mice that were fed a diet high in omega-3 and omega-6 fatty acids showed a significantly larger growth in fetus brains. Mice fed without those fatty acids showed smaller, more underdeveloped brains. The study also mentioned that the full grown mice that had a lack of fatty acids showed high levels of anxiety and other abnormal emotional behavior.
The U.S. Food and Drug Administration also encourages pregnant women to eat fish, but in much smaller portions. The 2014 guidelines put the cap on no more than 12 ounces per week.
“I think that in general people should follow the current recommendations,” Julvez added. “Nevertheless this study pointed out that maybe some of them, particularly the American ones, should be less stringent.”
Director of Maternal Fetal Medicine at NYU Lagone Medical Center in New York, Dr. Ashley Roman, told Reuters that she agrees that fish and seafood are important for the brain development of the fetus. “I think what’s interesting about this study compared to some data previously is that they better quantify the relationship between how much fish is consumed in a diet and then the benefits for the fetus and ultimately the child,” she said.
Since the danger is the slow accumulation of mercury, Roman encourages pregnant women to choose the type of fish carefully as well. Typically, this includes fish such as salmon, tuna, shellfish, and mackerel. “We still recommend that women avoid fish that are highest in mercury like catfish, shark, swordfish and giant mackerel,” Roman said. “Typically the larger fish that have longer lifespans and they tend to concentrate more mercury in their tissue.”
