New research suggests that fish may indeed be “brain food”.

In a study of 135 mothers and their infants, researchers at
Harvard Medical School found that mothers’ fish consumption
during pregnancy aided fetal brain development. Overall, the
greater a woman’s fish intake during the second trimester, the
better her 6-month-old performed on a standard test of mental
development.

On the other hand, when mothers had fairly high mercury levels —
as measured in hair samples — their babies tended to have
relatively poorer test scores.

According to the researchers, fish can be a brain-healthy food
for women to have during pregnancy — but only if they eat
varieties likely to have little mercury contamination.

Environmental mercury is primarily a product of industrial
pollution. Most fish and shellfish have some level of mercury,
but certain large, long-lived fish are likely to accumulate high
levels of the pollutant, which can damage the developing fetal
brain. Some shark, swordfish, albacore tuna, king mackerel and
tilefish may be high in mercury.

However, fish provide a number of important nutrients, including
omega-3 fatty acids, which support fetal brain development.

When participants’ babies were about 6 months old, the
researchers gave them a test that measured their visual memory.
The test is a good way to measure the potential effects of fish
intake, the lead researcher said, because it looks at both brain
function and vision. Omega-3 fatty acids are essential in eye
development as well as brain development.

Overall, babies’ scores on the test climbed by 4 points for each
weekly serving of fish their mothers had during the second
trimester.

If you’re avoiding fish because of concerns about mercury, we
have the perfect solution for you. You can take fish oil capsules
that contain highly concentrated amounts of the beneficial
omega-3 fatty acids. Vital nutrients fish oil has been thoroughly tested by
independent labs for mercury, arsenic, cadmium, lead, rancidity
and a wide range of environmental pollutants. It passes all
specifications for acceptability and is one of the purest fish
oil products on the market.

Source: Oken, E et al, Maternal fish consumption, hair mercury,
and infant cognition in a U.S. Cohort, Environ Health Perspect.
2005 Oct;113(10):1376-80