 |
|
|
SEAFOOD DURING PREGNANCY: ANAYLZING BENEFITS AND RISKS
Pregnant women should eat fish but avoid seafood high in mercury levels,
according to a new study showing that maternal fish consumption during
pregnancy is linked to better cognitive skills in infants, while high mercury
levels are linked to poorer cognitive performance.
Emily Oken and colleagues studied the relationship of seafood, mercury, and
infant cognition using subjects from Project Viva, a large-scale prospective
study of pregnancy and infant development. The researchers acquired data
about the dietary habits of 135 pregnant women and measured the women's
mercury levels using hair samples. They then tested the women's infants at six
months of age, using a visual recognition memory (VRM) test that is highly
predictive of later IQ.
The researchers report, "For each additional weekly fish serving, offspring
VRM score was 4.0 points higher. However, an increase of 1 ppm [part per
million] in mercury was associated with a decrement in VRM score of 7.5
points." VRM scores were highest in infants whose mothers ate fish more than
twice a week but had mercury levels below 1.2 ppm, a finding that remained
true when the researchers controlled for a wide range of sociological and
biological variables.
"It may seem contradictory that, on the one hand, fish intake raises mercury
levels and higher mercury levels lead to worse cognition but, on the other hand,
higher fish consumption is associated with better cognition," Oken and
colleagues say. "The most likely explanation is that the benefit is conferred by
consuming fish types with the combination of relatively little mercury and high
amounts of beneficial nutrients."
-----
"Maternal fish consumption, hair mercury, and infant cognition in a U.S.
cohort," Emily Oken, Robert O. Wright, Ken P. Kleinman, David Bellinger,
Chitra J. Amarasiriwardena, Howard Hu, Janet W. Rich-Edwards, and Matthew
W. Gillman, Environmental Health Perspectives, Vol. 113, No. 10,
October 2005. Address: Emily Oken, Department of Ambulatory Care and
Prevention, Harvard Medical School and Harvard Pilgrim, 133 Brookline
Avenue, Boston, MA 02215, emily_oken@harvardpilgrim.org.
|
|
