Swedish researchers found that among nearly 5,000 15-year-old boys they surveyed, those who ate fish more than once per week tended to score higher on intelligence tests three years later.
The findings, published in the journal Acta Pediatrica, add to evidence that fish may indeed be brain food.
Researchers believe that the omega-3 fats found in fish — particularly oily fish like salmon, mackerel and, to a lesser extent, albacore tuna — are important to early brain development and to maintaining healthy brain function throughout life.
Past studies have found, for instance, that children whose mothers who ate fish regularly during pregnancy tend to have higher intelligence scores than their peers, and older fish-eaters have been shown to have a lower risk of cognitive impairment.
The new study appears to be the first large-scale one to look at the effects of fish on teenagers’ intelligence, lead researcher Dr. Maria Aberg, of Goteborg University, told Reuters Health.
This is important, she explained, because the late-teens are a critical period for the brain “plasticity” that underlies intelligence and emotional and social behavior. Plasticity refers to the brain’s ability to reorganize the connections among cells in response to normal experience, like learning a new skill, or to injury.
The findings are based on data from 4,792 male adolescents who completed detailed questionnaires on diet and lifestyle when they were 15 years old, then underwent standard intelligence tests when they were 18.