New research shows that children who eat less seafood are more likely to struggle with kindness and social interaction. Could increasing fish intake be the key to raising more prosocial kids?
Study: Seafood intake in children at age 7 years and neurodevelopmental outcomes in an observational cohort study (ALSPAC). Image Credit: gorillaimages / Shutterstock
In a recent article published in the European Journal of Nutrition, researchers explored how eating seafood affects children’s behavior and cognitive outcomes. Their findings indicate that children between seven and nine who ate less seafood were significantly less likely to display ‘prosocial behaviors’—such as volunteering or showing consideration for others—compared to those who ate more seafood.
Background
Diet is critical for children’s brain development, and seafood, in particular, is rich in essential nutrients such as vitamin D, choline, selenium, iodine, protein, and long-chain omega-3 fatty acids.
While the body can produce some omega-3 fatty acids, dietary intake is necessary to maintain adequate levels. These nutrients support overall growth, hormone regulation, and brain function.
A 2023 report by the World Health Organization and the Food and Agriculture Organization highlighted the advantages of consuming seafood for people of all ages, though concerns about contaminants such as heavy metals and other toxins like dioxins and PCBs must be considered. This tension between the nutritional benefits and potential risks may contribute to low seafood consumption in children.
In the United Kingdom, guidelines recommend feeding children at least two portions of fish each week, including one portion of oily fish, but surveys suggest that actual consumption is far lower, which could limit their intake of critical nutrients. For example, the median seafood intake in the study was 123 grams per week, below the recommended 190 grams.
Though research suggests that maternal seafood intake during pregnancy has positive effects on children’s development, far fewer studies have examined the effects of seafood consumed directly by children, making this area of research important to explore.
About the study
Researchers examined how seafood intake by seven-year-olds related to cognitive outcomes in terms of intelligence quotient (IQ) scores at the age of eight and behavioral development in terms of scores on the Strengths and Difficulties Questionnaire (SDQ) at age seven and nine.
They defined suboptimal IQ as those with the lowest 25% of scores and suboptimal SDQ as those with high or very high difficulties with behavior and low or very low scores for prosocial behavior.
They utilized data from a large study conducted in the United Kingdom, which included pregnant women with 14,541 enrolled pregnancies and 913 children who were added subsequently.
When participating children were seven, their caregivers recorded their seafood consumption, including oily fish, white fish, and shellfish, in a food frequency questionnaire. Seafood intake was initially calculated in grams before being categorized as being up to two portions (if less than 190 grams per week), more than two portions (if 190 grams or more per week), or none.
The relationship between seafood intake and SDQ was assessed using logistic regression models and statistical tests. The models considered confounding factors such as breastfeeding, birthweight, maternal alcohol or cigarette use during pregnancy, maternal education, and the child’s sex.
Findings
After excluding participants with missing data from the analysis, the final sample comprised 5,969 children with IQ data, 8,276 with SDQ data at age seven, and 6,819 with SDQ data at age nine in addition to dietary data.
The participants included in the final sample were predominantly from affluent and predominantly white backgrounds. They were more likely to have mothers who drank alcohol while pregnant but less likely to have mothers who smoked. There were no significant differences between excluded and included children in terms of their seafood intake but included children were more likely to have mothers who consumed higher amounts of seafood while pregnant.
The median seafood intake for the children was 123g each week, with 7.2% eating no seafood, 63.9% eating up to two portions, and slightly under 29% eating more than two portions. White fish accounted for nearly half of the seafood consumption, and oily fish accounted for only 7%.
Researchers found no significant differences in IQ based on seafood intake. The study authors suggest that this may be because the age of 7 could be beyond the critical window for some aspects of neurodevelopment, that seafood intakes were generally low, or that the IQ measures used were not sensitive enough to detect subtle effects.
However, for behavioral scores, higher seafood intake was associated with higher prosocial scores (indicating more kindness or helpfulness) as well as fewer peer problems and less hyperactivity, though the most consistent and robust association was with prosocial behavior. These correlations were observed at ages seven and nine.
The regression model found more evidence of the link between prosocial behavior and seafood intake, which could be driven by nutrients such as omega-3 fatty acids, although the study found only a weak association when looking specifically at DHA intake.
Children aged seven who ate no seafood were 35% more likely (odds ratio 1.35) to have low scores for prosocial behavior, while those who ate up to two portions were 25% more likely (odds ratio 1.25) than those who ate more than two portions a week. This trend persisted at age nine with 43% and 30% higher odds, respectively. These are relative risks, not absolute changes in behavior.
Conclusions
While the research team found that eating more seafood during childhood was linked to better prosocial behavior and some improvement in peer relations and hyperactivity, no connections were seen with IQ. The benefits of seafood consumption may be related to essential nutrients such as omega-3 fatty acids, iodine, selenium, and choline, but the study emphasizes that DHA alone did not fully explain the behavioral outcomes.
These findings, in addition to previous studies that link seafood consumption to improved neurocognitive outcomes, can support the formulation of public health guidelines for fish consumption in children. However, the study’s reliance on a predominantly white, affluent participant sample, generally low seafood consumption levels, and possible unmeasured confounding factors are important limitations that should be addressed in future research.
The authors conclude that increasing seafood intake to recommended levels could help improve children's prosocial behaviors, but further research is needed to clarify its role in broader cognitive and behavioral development.