Seafood consumption during pregnancy may improve attention capacity in children

A team of scientists from the Barcelona Institute for Global Health(ISGlobal), a centre supported by "la Caixa," has studied the relationshipbetween the consumption of various types of seafood during pregnancy andattention capacity in children at eight years of age. The results, published in the _International Journal of Epidemiology_ , show that eating a seafood-rich diet during early pregnancy is associated with better attention outcomes in children. The study included 1,641 mother-child pairsfrom the INMA Environment and Childhood Project, a Spanish cohort study on therole of pollutants during pregnancy and their effects on children. Over thecourse of their pregnancies, the mothers completed numerous food-frequencyquestionnaires that assessed how often they ate more than a hundred differentfood items, including various types of seafood. Data on the children's dietaryhabits were also collected using the same questionnaire at one, five and eightyears of age. At eight years of age, the children also completed the AttentionNetwork Task (ANT), a computer-based neuropsychological test designed toassess attention function. The main ANT outcomes assessed by the researcherswere the number of omission errors committed in relation to target stimuli andthe speed of responses to stimuli. Both outcomes are commonly used asindicators of selective and sustained attention. The study builds on earlierresearch that analysed children at five years of age. "The consumption ofseafood during the first trimester of pregnancy had a greater effect onchildren's attention capacity than the consumption of seafood later inpregnancy or at five years of age, by which time some neurodevelopmentprocesses have already been completed," commented Jordi Julvez, researcher inthe Childhood & Environment programme at ISGlobal and lead author of thestudy. Brain development takes place mainly during pregnancy, through complexbiological processes such as neuron formation, synaptogenesis and myelination.Essential nutrients such as polyunsaturated fatty acids (PUFAs) play afundamental role in these processes. "Docosahexaenoic acid (DHA) andeicosapentaenoic acid (EPA) are the main omega-3 PUFAs involved inneurological development, and seafood is the main source of both of them,"added Julvez. Because these nutrients participate in the definition of foetal brain structure and function, they have a large impact on later neuropsychological development. Attention is a complex behaviour that allchildren must learn, since it precedes other crucial functions such as memory."We focused on the attention function because attention-deficit hyperactivity disorder is common in school-age children," commented Jordi Sunyer, head of the Childhood & Environment programme at ISGlobal. The study also assessed thedifferences between various types of fish and seafood: fatty fish, lean fish,canned tuna and shellfish. Children whose mothers ate a diet rich in varioustypes of seafood scored very well on the attention tests, as did children ofwomen with a diet rich only in fatty fish. However, scores were lower inchildren whose mothers relied on canned tuna or shellfish for their seafoodintake. The role of genetics in PUFA metabolism was one of the elementsanalysed in the study. "We observed differences in the effect of seafood onchildren's attention capacity as a function of genetic variations known assingle nucleotide polymorphisms (SNPs)," commented Julvez. The findingssuggest that some SNPs facilitate PUFA metabolism, thereby contributing tobetter attention outcomes, while others have a negative effect on PUFAmetabolism. Seafood consumption was shown to have a compensatory effect inchildren with SNPs that hinder PUFA metabolism. "Children with, for example,the rs1260326 CC genotype -- which has been associated with lower PUFA levels-- had worse attention scores if their mothers had not eaten much seafoodduring pregnancy," commented Julvez. "But their outcomes improved if theirmothers consumed more seafood." Despite the promising results of this study, the authors of previous research have reported a link between the consumption of fish during pregnancy and childhood obesity and increased blood pressure.Consequently, experts insist on the need for more research on this subject to determine exactly which species of fish and what quantities may be beneficial to fetal development.Story Source:Materials provided byBarcelona Institute for Global Health (ISGlobal).