New research conducted at the Penn State College of Medicine suggests that adding fish to a toddler’s diet may offer protection against neurodevelopmental delays. The study, which followed 142 children from birth to 18 months old, found that consuming fish at least once a week was associated with a decreased risk of neurodevelopmental delays. Interestingly, the positive effects of fish consumption on neurodevelopment appeared to be amplified by the child’s microbiome.
The findings of this study, published in the journal Microorganisms, indicate that the association between fish consumption and neurodevelopmental outcomes is not influenced by social or environmental factors. While genetics play a role in certain neurodevelopmental conditions, emerging evidence suggests that environmental factors and social determinants of health can interact with genes to impact neurodevelopment.
Terrah Keck-Kester, the first author of the study and assistant professor of pediatrics at Penn State, explained that their research highlights the potential impact of diet, specifically fish consumption, on neurodevelopmental outcomes. To assess the dietary habits of the infants, the team utilized the Infant Feeding Practices II Survey, which is a standardized questionnaire developed by the Food and Drug Administration and the Centers for Disease Control and Prevention. Saliva samples were also collected from the infants at 6 months to measure the activity levels of different bacteria.
The researchers chose saliva as the sample because it is easily accessible during well-child visits, is in close proximity to the developing brain, and represents one of the first areas of microbial contact for infants as they explore their physical world, according to Steven Hicks, the corresponding author of the study and associate professor of pediatrics at Penn State.
To determine the presence or absence of neurodevelopmental delays, the team relied on parental responses to a Survey of Wellbeing in Young Children, which is a screening instrument recognized by the American Academy of Pediatrics. The delays were defined as difficulties in skills development, such as running, speaking, and social interaction, observed in the children at 18 months old.
The results showed that neurodevelopmental delays were more prevalent in children who did not consume fish at 12 months old. Additionally, these delays were associated with increased activity of two specific salivary microbes—Candidatus gracilibacteria and Chlorobi.
Terrah Keck-Kester acknowledged the need to consider other variables that could potentially impact the findings, stating, “Are the findings more related to variables other than the ones being studied? For example, consider factors that determine whether a person is able to eat more fish in their diet. With our statistical analysis, we were able to control for many of these factors.”
The researchers also looked into social determinants of health, such as maternal stress, family income, and access to healthcare, as well as demographic contributions, including race, ethnicity, and age of home, which could potentially influence neurodevelopmental outcomes. The study found that Hispanic children were more likely to face neurodevelopmental challenges.
Ultimately, the study concluded that beyond social and environmental factors, children who consumed fish at least once a week were less likely to exhibit neurodevelopmental delays at 18 months old. Furthermore, the protective effect of fish consumption on neurodevelopment appeared to be enhanced by microbial diversity.
Steven Hicks highlighted the potential role of microbial diversity in the metabolism and utilization of essential nutrients, such as long-chain polyunsaturated fatty acids, which are associated with fish consumption. These findings shed light on the importance of considering dietary factors and microbial diversity in promoting optimal neurodevelopmental outcomes in early childhood.