Children Whose Mothers Ate Fish in Pregnancy Are Less Hyperactive
Many studies have reported a variety of desirable outcomes in children whose mothers ate fish during their pregnancy compared with children whose mothers did not eat fish. More recently, studies have noted better childhood performance scores when their mothers ate more fish than is recommended by the US government, i.e., more than 340 g (12 oz)/week. Benefits have been observed in cognitive test scores, mental processing, behavior and motor function among others. Thus, it is becoming more difficult to defend recommendations that pregnant and nursing women should limit their fish consumption, provided they are not eating fish with high levels of contaminants, particularly mercury. The more worrying problem is that most women in developed countries eat too little fish.
A new report from researchers at the University of Southampton, U.K., describes the relationship between a mother’s fish consumption during pregnancy and the intelligence and behavioral scores of their children at age 9. The investigators noted that mothers who ate fish, especially fatty fish (e.g., salmon, tuna, rainbow trout, sardines), while pregnant tended to be more educated, older, and have higher intelligence scores and socioeconomic status compared with mothers who did not eat fish. They were less likely to smoke and more likely to breastfeed longer as well.
At 9 years old, children whose mothers ate fish less than once/week were less likely to exhibit hyperactivity compared with children whose mothers did not eat fish. Social, emotional and total intelligence scores did not differ between the two groups. However, the children whose mothers ate fish once or twice a week or less had significantly higher verbal intelligence scores compared with children whose mothers did not eat fish. Verbal intelligence scores increased as the mother’s fish intake rose. This observation supports a previous report from another UK study that linked children’s intelligence scores with greater maternal fish consumption in pregnancy. In both studies, no adverse effects were observed in any of the children’s performance assessments as the mother’s fish consumption increased. This observation suggests that the fears associated with exposure to contaminants from maternal fish consumption are exaggerated.
Although the relationships between maternal fish consumption and less hyperactivity and higher verbal intelligence scores in their 9-year old children were significant, the possibility that these findings might relate to the children’s own fish consumption cannot be ruled out. The assumptions for a credible link between a mother’s diet and her child’s development rest mainly on the importance of the transfer of long-chain polyunsaturated fatty acids to the fetus, especially of the seafood omega-3 docosahexaenoic acid (DHA). These fatty acids are critical for the structure and function of the brain, which undergoes rapid development in the third trimester and early years of life. Lower brain DHA has been reported in the children of mothers who do not eat fish during pregnancy. Still, it is remarkable—yet plausible—that the mother’s diet in pregnancy has long-lasting effects on child development.
SOURCE: Fats of Life Newsletter