Fish is the primary dietary source of omega-3 fatty acids. Omega-3
fatty acids are essential nutrients that we can’t synthesize, we have to eat. Because they are necessary for optimal fetal
brain, eye development it’s recommended for pregnant women to consume a high
amount of fish. However.
Most man-made emissions are released from burning coal laced
with mercury. Mercury moves through the
air and is deposited in water and finds its way into fish, accumulating
especially in fish that are higher up the food chain.
Mercury can cross the placenta to harm the rapidly
developing nervous system, including the brain. Studies (in Boston, New York, Krakow, Seychelles
Islands, Granada, etc) associated
prenatal methylmercury exposure with
impaired developments of sensory, motor, and cognitive functions,
resulting in learning difficulties, poor coordination and inability to
concentrate.
Therefore pregnant women and nursing mothers should be aware
of better and worst choices when it comes to seafood items, so they can choose
wisely: E.g. low mercury choices include shrimp, salmon, sardines, tilapia, scallops, clams and mussels, pollock,
crabs, catfish flounder and sole.
Generally high mercury levels were found in tuna, marlin,
shark, barracuda and swordfish.
(Sources: Emily Oken, MD, MPH, Harvard Medical School – Perspective
on potential benefits and harms of fish consumption; Edward Groth, PhD for Zero
HG An Overview of Epidemiological Evidence on the Effects of Methylmercury on
Brain Development, and a Rational for a Lower Definition of Tolerable Exposure;)