A study in the March 2003 Pediatrics demonstrates that children born to mothers who had taken cod liver oil, rich in DHA and other omega-3 fatty acids, during pregnancy and lactation scored significantly higher (approximately 4.1 points) on standardized intelligence tests than those whose mothers had received corn oil during the same period.

Researchers conducting the randomized, double-blind trial enrolled women during the 18th week of pregnancy and supplemented their diets with one of two different polyunsaturated fatty acids (PUFAs). Participants received either cod liver oil (containing a PUFA rich in DHA and other omega-3 fatty acids) or corn oil (a PUFA with no DHA content) from the point of enrollment until three months after childbirth. Researchers later completed assessments of intelligence for 84 child subjects once they reached four years of age. http://content.intramedicine.com/LNR/factoids/?factID=271