Fish is high in protein and low in saturated
fat, particularly white-fleshed species including cod, halibut,
and tilapia. It’s also full of health-boosting “good”
fats –omega-3 fatty acids.
3s, especially prevalent in fatty coldwater fish (herring, mackerel,
salmon, trout, and tuna), benefit the body in many ways. These
fats may help prevent heart disease, heart attack, and stroke,
and they aid pre- and postnatal neurological development. Older
brains need omega 3s, as well. One study of elderly people found
that annual mental decline was 10 percent slower in those eating
fish at least once a week. These powerful fatty acids may benefit
those suffering from arrhythmia, depression, irritable bowel syndrome,
and rheumatoid arthritis. They may even help prevent Alzheimer’s
Despite the many health benefits of fish consumption,
83 percent of Americans- some likely scared off by warnings of
contaminants-do not eat the two servings a week recommended by
many experts. Two contaminants in particular, mercury and PCBs,
have received significant press in relation to seafood. Emitted
primarily by industrial sources, mercury winds up in water and
enters the tissue of fish in a form called methylmercury. As big
fish eat smaller ones, methylmercury moves up the food chain and
biomagnifies (grows more potent). Fish at the top of the food
chain, such as swordfish and shark, typically contain the highest
concentrations of methylmercury.
Excessive mercury can affect the human nervous
system and kidneys. Many experts believe that fetuses, infants,
and young children, whose nervous systems are still maturing,
are especially at risk and can sustain developmental and neurological
damage as a result of overexposure.
Because of the perceived danger, the U.S. Food
and Drug Administration (FDA) and the Environmental Protection
Agency (EPA) issued a joint warning in 2004 advising mothers-to-be,
nursing mothers, and small children to avoid the high-mercury
species king mackerel, shark, swordfish, and tilefish. However,
this same population was encouraged to continue eating 12 ounces
per week of low-mercury seafood including salmon, shrimp, and
canned light tuna.
Polyychlorinated byphenyls (PCBs) prohibited
for U.S. manufacturers in 1977 but still present in the atmosphere
and waterways, are also a concern. Like mercury, PCBs were released
into the environment by industrial sources and continue to build
up in the tissue of fish. Also like mercury, these substances
may have negative developmental and neurological effects on fetuses
and children. PCBs have also been linked to breast cancer and
The FDA’s advisory created and unexpected
backlash: Some health experts believe the American public misheard
the warning as, roughly, “watch our for fish!” A recent
study by the University of Maryland’s Center for Food, Nutrition,
and Agriculture Policy showed that many adults didn’t understand
the warning, knowing neither who should fish nor what fish to
as a result of these misconceptions, many Americans are missing
out on the crucial benefits fish offer. The realty is that experts
still recommend two servings of fish a week. Limit consumption
to the low-mercury species. Also keep in mind that selenium, found
in many ocean fish, neutralizes mercury’s toxicity in the
body, as does natural vitamin E.
When issuing its 2004 warning to pregnant and
nursing women, the FDA noted that canned light tuna- a type of
tuna called skipjack-was an acceptable low-mercury fish (skipjack
contains about one third of the mercury found in albacore). However,
a recent Chicago Tribune story alleged that approximately 15 percent
of light tuna sold, sometimes but always labeled “tonno”
or “gourmet,” is not skipjack but yellowfin, a potentially
toxic tuna species. Since then, the FDA has released test results
showing that 6 percent of light tuna tested contained high levels
of mercury. The FDA is still investigating the yellowfin allegations.
Wild Caught or Farm Fresh?
Salmon, low in mercury and high in omega-3 fats,
seems an ideal choice for the health conscious. However, a debate
about the merits of wild-caught versus farmed salmon continues
to confuse consumers. PCBs and other contaminants sit at the heart
of the debate. Farmed salmon contain notably higher levels of
PCBs than wild-caught salmon. Additionally, because farmed salmon
are raised in close quarters, they are prone to disease epidemics
and, for this reason, are often treated with chemicals.
One gourmet chain had committed to purchasing
only farmed king salmon that meets strict contaminant and environmental
guidelines; natural product stores carry wild-caught fish. Some
experts recommend wild-caught salmon for pregnant/nursing women
and young children.
When shopping, choose fresh fish with firm, translucent
flesh. Avoid fish with spots or bruises, as well as cloudy eyes,
which could signal bacteria and/or decomposition. When opting
for frozen fish-an excellent choice with the advent of flash freezing-make
sure fish is hard, with no freezer burn. If purchasing lobsters
or crabs, choose fresh caught rather than buying from a tank.
Pick up seafood at the end of any shopping trip.
preparing fish, remove the skin, fat, and internal organs-all
places where toxins build up. This reduces levels of PCBs and
other toxins, but not mercury. Wash hands and cooking tools during
preparation, and keep raw seafood away form other food. Let fat
drain away from the fish while cooking, and avoid frying, which
seals in toxins, cook thoroughly.