Dec. 21 (UPI) -- Kids who eat fish at least once a week score higher on IQ tests and experience better sleep, according to new research by scientists at the University of Pennsylvania.
Omega-3s, fatty acids found in fish, have previously been linked individually to boosts in intelligence and improved sleep. But the latest study -- published this week in the journal Scientific Reports -- is one of the first to examine the relationship between all three variables.
"This area of research is not well-developed. It's emerging," Jianghong Liu, an associate professor of nursing and public health at Penn, said in a news release. "Here we look at omega-3s coming from our food instead of from supplements."
The study included 541 children in China, ages nine to 11, 54 percent boys and 46 percent girls. Each child answered survey questions about their fish consumption and dietary habits. They also completed the Wechsler Intelligence Scale for Children-Revised, the Chinese version of an IQ test. Parents answered questions about their children's sleeping habits.
Children who ate fish at least once a week scored 4.8 points higher on the IQ test than kids who said they rarely or never ate fish. Those who ate fish sometimes scored 3.3 points higher. The data also showed children who ate fish regularly experience fewer nighttime disruptions of sleep.
Researchers say the correlation between sleep, intelligence and fish consumption was strong even after they controlled for a variety of sociodemographic factors.
The findings suggest sleep may serve as the mediating pathway by which fish consumption boosts cognitive performance.
"Lack of sleep is associated with antisocial behavior; poor cognition is associated with antisocial behavior," said Adrian Raine, a professor and researcher at Penn. "We have found that omega-3 supplements reduce antisocial behavior, so it's not too surprising that fish is behind this."
Researchers suggest a concerted effort be made to increase fish consumption among young children.
"Introducing the taste early makes it more palatable," said Jennifer Pinto-Martin, executive director of Penn's Center for Public Health Initiatives. "It really has to be a concerted effort, especially in a culture where fish is not as commonly served or smelled. Children are sensitive to smell. If they're not used to it, they may shy away from it."