Higher blood levels of omega-3s -- fish body oil -- are associated with better reading and working memory performance in children, British researchers say. Researchers at the University of Oxford in England said the findings indicated increased dietary intake of omega-3s might be beneficial for healthy children ages 7-9, who are underperforming in school. The study involved 493 healthy children ages 7-9 recruited from mainstream state schools in Oxfordshire underperforming in literacy skills, but with other abilities within the normal range. The study, published in the journal PLoS One, found blood samples, taken through the first-ever finger stick test administered to children in Britain revealed the sample population had on average a blood fatty acid level of 1.90 percent of DHA and 0.55 percent of EPA with a total of 2.46 percent combined DHA and EPA omega-3 fatty acids. Leading scientist say a minimum of 4 percent is recommended to maintain cardiovascular health in adults, the researchers reported. The study found lower DHA concentrations were associated with poorer reading ability and working memory performance. In addition, lower DHA was associated with higher levels of parent-rated oppositional behavior and emotional adaptability. The researchers asked each child\'s parents about his or her child\'s diet and found that 88.2 percent of children ate fish less than twice a week and 9 percent did not eat fish at all. The study was funded by a grant from DSM Nutritional Products.