(02-04-07) Essential Fatty Acids & Omega-3 Fats on Child, Adult & Maternal Health :

Fish Oil in Pregnancy Linked to Enhanced Toddler Eye and Hand Coordination
The high concentration of docosahexaenoic acid (DHA) a long-chain omega-3 polyunsaturated fatty acid (n-3 LC-PUFA) in the brain and its involvement in neurotransmission, visual acuity and cognitive development in the infant have focused attention on the nutritional adequacy of maternal and infant diets as a source of this fatty acid. In the fetal period, DHA is furnished from the mother's diet and stores. Western diets are often low in fish, so pregnant and nursing women may have insufficient intake of n-3 LC-PUFAs to meet their own needs and those of their infants. After birth, the infant obtains n-3 LC-PUFAs from breast milk or DHA-supplemented infant formula. Term infants have some LC-PUFAs available from their body fat stores.

Several studies have reported improved scores for visual acuity and various neurodevelopmental outcomes in DHA-supplemented term infants, but there are few reports of long-term benefits from n-3 LC-PUFA supplementation during pregnancy or early infancy. Thus, questions of long-term and transient benefits remain.

Supplementation with n-3 LC-PUFAs typically reduces the content of the n-6 LC-PUFA arachidonic acid (ARA) in cell membranes. To ensure that DHA supplementation would have no adverse effect on ARA metabolism, infant formula is often supplemented with both DHA and ARA.

Dr. Jan Dunstan and colleagues at the University of Western Australia in Perth investigated the long-term effects of maternal consumption of 4 g/day of fish oil or olive oil during pregnancy from the 20th week of gestation until delivery. The fish oil capsules provided 1.1 and 2.2 g/day of eicosapentaenoic acid (EPA) and DHA, respectively. This level of n-3 LC-PUFA consumption would be about 3 times the amount in a single serving of salmon.

Eighty-three of 98 participating mothers completed the study and 72 healthy children, born after at least 36 weeks' gestation, were available for assessment at 2? years of age. Outcome measures included mental development (Griffiths Mental Development Scales), receptive language (Peabody Picture Vocabulary Test) and behavior (Child Behavior Checklist). The Griffiths test includes 6 individual subscales and a quotient of the mean subscale measurements. The Peabody test evaluates listening comprehension of standard English vocabulary. The Child Behavior Checklist measures parental perception of the child's competencies and behaviors. The investigators measured phospholipid fatty acids in the red blood cells of cord blood of infants who completed the cognitive assessments. Mothers consuming fish oil were similar to those taking olive oil, except they were slightly younger (30.9 vs 32.6 years, P= 0.05).

Children from both groups of mothers did not differ in height, weight or head circumference. As expected, red cell phospholipid fatty acids in the fish oil group had increased n-3 LC-PUFA and reduced ARA concentrations compared with the controls (Table 1).

Scores from the Griffiths Mental Development assessment revealed no differences in the overall scores between the fish oil and control groups, nor in 5 of the 6 subscales (Table 2). However, scores for eye and hand coordination were significantly higher in the children of fish oil mothers compared with controls (114.0 ? 10.2 vs. 108.0 ? 11.3, P=0.02). When the scores were compared taking into consideration potentially confounding variables, this difference remained statistically significant. Scores from the Peabody test for language and the behavior checklist indicated no significant differences between the two groups.

The authors examined the relationship between individual red cell fatty acids in cord blood and cognitive outcomes for the whole sample. They observed a significant relationship between EPA, DHA and the ratio of n-3 to n-6 PUFAs and eye and hand coordination (P=0.01). There was a significant inverse relationship with ARA at age 34 months. The correlations were independent of potentially confounding factors, such as maternal education and duration of breastfeeding.

Of the 72 children in this study, 91% from the fish oil group and 95% from the control mothers were breast fed for an average of 8.8 and 7.5 months, respectively. These differences were not statistically significant. The enhanced eye and hand coordination of children of fish oil-fed mothers was positively associated with cord red blood cell EPA and DHA concentrations. No other cognitive scores were significantly associated with red cell fatty acids. Improved eye and hand coordination would be consistent with improved visual function in infants fed n-3 LC-PUFA-supplemented infant formula and increased mental processing in children whose mothers consumed DHA during pregnancy as reported by others.

Two comments are pertinent. One is the relatively high dose: 4 g/day total n-3 LC-PUFAs. Other studies using smaller amounts of n-3 LC-PUFAs have reported positive outcomes associated with the consumption of these fatty acids, suggesting that these findings may not have depended on the high dose. The other comment is that Griffiths mental development scores in all tests for the children whose mothers consumed fish oil were consistently, but not statistically significantly, higher than in control children (Table 2). A larger sample might have provided the statistical power needed to determine whether n-3 LC-PUFAs consumed during pregnancy would have affected other developmental outcomes. The authors also noted that the relatively high dose was not associated with any adverse effects or interference with n-3 PUFA metabolism. These findings are good news for those worried about consuming too much of a good thing.

Dunstan JA, Simmer K, Dixon G, Prescott SL. Cognitive assessment at age 2? years after maternal fish oil supplementation in pregnancy: a randomized controlled trial. Arch Dis Child Fetal Neonatal Ed 2006; doi: 10.1136/adc.2006.099085

Fonte: PubMed

News

---

In evidenza

"L'informazione presente nel sito serve a migliorare, e non a sostituire, il rapporto medico-paziente."

Per coloro che hanno problemi di salute si consiglia di consultare sempre il proprio medico curante.