The National Academies of Sciences, Engineering, and Medicine (NASEM) has released the final version of their report on the role of seafood in child growth and development. The report weighs the nutritional benefits of seafood consumption against the health risks of dietary exposure to contaminants in seafood, with particular consideration for pregnant or breastfeeding women and their children. Children’s growth and development are particularly vulnerable to excessive exposure to contaminants in the diet.
The report was commissioned by the U.S. Food and Drug Administration (FDA) to inform the agency’s “Closer to Zero” initiative and to develop advice on eating fish in collaboration with the U.S. Environmental Protection Agency (EPA).
Seafood is a unique and rich source of several important nutrients. Dietary Guidelines for Americans Recommendation U.S. adults should aim to eat two 4-ounce servings of seafood per week. For children, guidelines recommend introducing seafood from age 6 months, and then two servings per week proportional to their total calorie intake.
At the same time, seafood often contains harmful contaminants from the environment, including methylmercury, perfluoroalkyl substances (PFAS), polyfluoroalkyl substances (PFAS), persistent organic pollutants such as dioxins and polychlorinated biphenyls (PCBs), and microbiological hazards. Mercury and PCBs are the most important factors behind fish consumption advisories.
In general, NSAEM concluded that there is currently insufficient evidence to support revising fish and shellfish consumption recommendations. Dietary Guidelines for AmericansIt is also not possible to assess the health risks from exposure to contaminants in seafood other than mercury.
The report noted that adults and children who eat a lot of seafood have higher concentrations of mercury and some forms of arsenic. Yet, most commonly consumed fish in North America, with the exception of some tuna, have low levels of methylmercury. Furthermore, with the exception of frequent tuna eaters, the average intake of mercury from seafood among women of childbearing age, infants, and children is below the FDA’s “near-zero” limit. High concentrations of other toxic heavy metals and contaminants are limited to certain species and regions. For example, PCBs are a particular problem in the Great Lakes region.
Evidence supports that fish consumption by breastfeeding mothers may have positive effects on the health of their children, including improved cognitive, behavioral and language development, but there is insufficient evidence to establish an association between children’s seafood intake and their overall health.
The report calls for FDA to routinely monitor evidence and methods for evaluating the risks and benefits of seafood to child development. There are many knowledge gaps about the health effects of exposure to contaminants from seafood consumption. For example, it is unclear whether nutrients and contaminants in seafood affect children’s health differently depending on the species, source, or location; whether there are specific periods in children’s development when seafood consumption may have different effects on children’s health; and, most generally, what effects children’s health may have when they consume seafood. Importantly, further characterization is needed to inform risk assessments of chronic exposure to less-studied contaminants, such as PFAS, arsenic species, microplastics, and domoic acid.
