Children who frequently ate fish showed higher IQ scores and reported fewer sleep problems than their counterparts who seldom or never ate fish, according to findings recently published in Scientific Reports.
“To our knowledge, no study has simultaneously examined how dietary fish and omega-3 fatty acid intake affects sleep and cognition,” Jianghong Liu, PhD, RN, FAAN, associate professor, University of Pennsylvania Schools of Nursing and Medicine, and colleagues wrote. “Furthermore, studies of dietary omega-3 fatty acid consumption in school-aged children examining cognition and sleep have primarily been limited to Western countries, with the latter relationship only reported by one study to date in healthy school-aged children.”
Researchers conducted a longitudinal study of 541 children from an existing study cohort in China. Fifty-four percent of participants in the current study were boys. The children were aged 9 to 11 when researchers measured their sleep quality and fish consumption, and they calculated IQs at age 12. Apart from the children’s home location and paternal education, there were no significant differences in their social demographic features.
Liu and colleagues found that children who ate fish at last once a week had IQ scores that were 4.8 points higher than those children who ate it less than two times a month; also, children who ate fish two to three times a month had IQ scores that were 3.31 points higher than those children who ate it less than two times a month. Further, sleep quality somewhat mediated the relationship between fish consumption and verbal, but not performance, IQ. Researchers also wrote that findings were robust after controlling for 13 sociodemographic covariates.
“We believe that the findings cannot be easily attributed to chance and that instead, they reflect a reliable relationship between early frequent fish consumption and later improved cognitive performance,” Liu and colleagues wrote. “Importantly, our findings are also novel in demonstrating that sleep may serve as a mediator between frequent fish consumption and improved cognitive ability, providing an important mechanism by which fish consumption may affect cognitive functioning. To our knowledge, this is the first study to identify and demonstrate such a mediating effect.”
“[These results add] to the growing body of evidence showing that fish consumption has really positive health benefits and should be something advertised and promoted,” Jennifer Pinto-Martin, PhD, MPH, executive director of the University of Pennsylvania’s Center for Public Health Initiatives, said in a press release.
The release also stated that children should be introduced to fish no later than their second birthday.
Researchers said future studies should measure fish consumption, sleep patterns and IQ at different time periods in children; type of fish consumed; and the mechanisms through which consuming omega-3 fatty acids possibly lead to enhanced neurodevelopment and cognitive function. – by Janel Miller
Disclosure: The authors report no relevant financial disclosures.