TUESDAY, Sept. 20, 2011 (HealthDay News) -- Whether they're fed by bottle or breast, babies seem to turn out smarter when nourished with healthy fatty acids found in breast milk and some formulas, two new studies indicate.
The studies, done in the United Kingdom and Spain and published online Sept. 19 in the journal Pediatrics, found that higher levels of long-chain polyunsaturated fatty acids (such as DHA, EPA and ALA) were linked to greater mental development in both young and older children.
Breast milk contains these substances naturally, and many infant formulas have been fortified with healthy fatty acids since research in the last two decades began to suggest they enhanced babies' brain development.
"The longer a mother can breast-feed as exclusively as possible, the better. But if for whatever reason mother can't keep up with nutritional needs of the infant . . . formula definitely offers a great alternative, especially since they supplement formulas these days with long-chain fatty acids," said Dr. Roya Samuels, a pediatrician at Cohen Children's Medical Center in New Hyde Park, N.Y., who was not involved in the studies.
The U.K. research team analyzed 107 formerly preterm infants who were about 10 years old at the time of the study. Between birth and 9 months of age, they had been randomly split into groups that received formula supplemented with fatty acids or a placebo. Some also were nourished with breast milk during that time.
During extensive testing measuring IQ, memory, attention and other cognitive functions, the children who exclusively received supplemented formula showed benefits in several cognitive measures. Also, girls -- but not boys -- demonstrated significant advantages in literacy, including reading and spelling. The apparent gender effects concur with growing research describing differences in boys and girls in the brain's vulnerability to outside forces, including nutrition, the study authors said.
"To me, as a neuropsychologist, this must mean the effects on the neural structures supporting reading are different in the two sexes," said lead author Elizabeth B. Isaacs, a senior research fellow at the Childhood Nutrition Research Centre at University College London's Institute of Child Health. "There appear to be differences in how fatty acids are metabolized between genders, so that might be involved. But we really don't know, and the answer, as always, is that more research is needed."
The findings should be interpreted cautiously because of the small size of the study. Also, two of Isaacs' co-authors reported receiving funding from formula manufacturers.
The Spanish study found that higher amounts of breast-feeding among all milk consumed during children's first 14 months was associated with significantly higher mental scores compared to children who breast-fed less. Researchers recruited women during their first trimester of pregnancy, measured fatty acids in their colostrum after childbirth, and assessed mental development of more than 500 children at about 14 months of age.
Maternal education, social class and IQ only partly explained the association, according to the study authors, leading them to conclude that long-chain fatty acid levels benefited children, especially those breast-fed for longer durations.
Commenting on the study, Samuels said several factors could explain the Spanish research team's assertions about breast-feeding, not just the nutritional content of the milk.
"It's very hard to attribute the improved neurodevelopment in children to a specific ingredient in breast milk, which I think the study is trying to do," she said. "We can take away from this that a lot more study is required in this field to get a grasp on exactly what it is about breast-feeding that leads to [these effects]. The actual act of breast-feeding and developing an intimate relationship with your child is really critical to raising a healthy newborn . . . not to say a formula-fed baby is at any risk for impairment, but there's something unique and special about the act of breast-feeding itself," Samuels added.
The Franklin Institute has more information about fatty acids and brain effects.