Is Eating Fish Safe
by Wendy Priesnitz
Awhile back, I read that there had been new research saying that pregnant and
breastfeeding women should eat a minimum of 12 ounces of fish per week. But I’d
previously thought that should be the maximum because of mercury contamination
and its negative effect on babies’ development. Can you clear up this confusion?
The report you’re probably referring to came from a
Virginia-based organization called National Healthy Mothers, Healthy Babies
(HMHB). Their recommendation to eat at least 12 ounces (340 grams) or three to
four servings per week of fish was based on a review of scientific studies that
indicated a positive link between ocean fish consumption and advanced cognitive
and motor skill development in children. What the group seems to have ignored is
the problem with mercury and other contaminants, which is the basis of the U.S.
Food and Drug Administration’s advisory that pregnant and nursing women should
eat no more than 12 ounces per week of certain types of fish and eliminate
You are not the only one confused about this new
recommendation. The HMHB announcement was, in fact, received with a great deal
of negativity by health and environment organizations. For instance, the
Washington D.C.-based Environmental Working Group (EWG) took a strong stand
against the recommendation, disputing the quality of the results and noting that
the study was funded with $60,000 from the National Fisheries Institute, a
seafood industry group. “It’s important when you read these kinds of reports to
take a close look at who is funding the research,” says Jovana Ruzicic, a
spokeswoman for the EWG.
We feel it’s also prudent to consider the source of (and
possible motivation behind) recommendations resulting from research. HMHB’s
Chair is George Guido who is Director of Public Affairs for AstraZeneca, which
is one of the world’s largest pharmaceutical companies. Its Vice Chair is
Hampton Shaddock who is the Managing Director, Health Care for
Burson-Marsteller, which is one of the world’s largest PR companies.
Burson-Marsteller has a history of creating industry-funded “organizations”
designed to manage information and public opinion on controversial subjects. In
the U.S., it helped Philip Morris set up the National Smokers Alliance in the
early 1990s and has done work for the National Cattlemen’s Beef Association,
McDonalds and other large corporations; it also has ties to the George W. Bush
There is no doubt that fish is an
excellent source of high quality protein and is low in saturated fat and
cholesterol. It is also an excellent source of omega 3-fatty acids, which have
proven neurological benefits. Unfortunately, many types of fish are contaminated
with the legacy of a century of industrialization, particularly mercury, dioxin
and PCBs. For instance, research conducted at Harvard and published in
Environmental Health Perspectives
in 2005 found that: “Higher fish consumption in pregnancy was associated with
better infant cognition, but higher mercury levels were associated with lower
cognition. Women should continue to eat fish during pregnancy but choose
varieties with lower mercury contamination.”
The problem is that the research
results are inconclusive and inconsistent. However, a new study – the Pregnancy
Outcomes and Community Health study, conducted at Michigan State University and
also published in Environmental Health Perspectives
– suggests an increased risk of pre-term delivery in relation to mercury
concentrations among women with low to moderate exposure.
We also know that omega-3 and omega-6 fatty acids are not
synthesized by the body and therefore must be obtained through diet or
supplementation. Oily fish, such as mackerel and salmon, yield a complex type of
omega -3, which is made up of two types of acids: EPA (eicosapentaenoic acid)
and DHA (docosahexaenoic acid) and is well suited to human requirements.
However, simpler omega-3 fatty acids are found in a variety of plant sources.
They are called ALAs (alpha-linolenic acid) and can be converted in our bodies
into EPA and DHA.
Plant based sources of omega-3 fatty acids include: leafy
green vegetables like seaweed, broccoli, spinach, kale, spring greens, cabbage,
Brussels sprouts and parsley; nuts like walnuts, Brazil nuts, hazelnuts and
pecans; egg yolks; seeds like flax, pumpkin and sesame; and oils like soy,
canola, flaxseed and hemp. Hemp oil is especially good, since it contains
omega-3 and omega-6 fatty acids in the ratio required by our bodies. Prepared
foods like bread, juice, meal bars, margarine and oils are available containing
omega-3s, as are non-fish oil-based supplements. Since pesticides concentrate in
fats and oils, buy organic whenever possible.
In addition to the concerns about mercury contamination of
fish, consumers should consider the ecological concerns and sustainability
issues regarding various global fisheries, including aquaculture (fish farming).
In 2005, a United Nations comprehensive ecosystem assessment found that the
exploitation of global fisheries is now well beyond levels that can be sustained
at current or future demands. The effects are being seen in polluted waters, the
depletion of many stocks and a sharp decline in the diversity of species. While
aquaculture has the potential to be a more sustainable method of seafood
production, the industry has faced allegations of significant environmental
So if you feel that you must eat fish before or during
pregnancy, or while breastfeeding, be careful what kind and how much...and
consider the alternatives.
What Seafood is Safe to Eat if You’re
Pregnant or Nursing?
Fat soluble contaminants (such as dioxins
and dioxin-like compounds) are especially found in fatty fish, e.g. salmon
and herring. Methymercury levels are not related to the fat content of the
fish but, due to its accumulation in the food chain, methylmercury is
present in higher amounts in large predatory fish (such as swordfish and
Consume a maximum 12 ounces ( 340 grams) a
week of varieties of fish and shellfish that are lower in mercury, such as
shrimp, canned light tuna, wild Pacific salmon, pollock and catfish.
Albacore (“white”) tuna has more mercury
than canned light tuna, which is prepared from smaller fish. Albacore tuna
should be limited to no more than six ounces (170 grams) per week.
Avoid shark, swordfish, king mackerel,
marlin, pike and tilefish (aka golden bass or golden snapper), fresh/frozen
tuna, orange roughy, non-Baltic herring.
Limit consumption of non-organically farmed
salmon to no more than one meal per month.
Sources: These recommendations are gathered
from the U.S. Food and Drug Administration, U.S. Environmental Protection
Agency, Health Canada and the European Food Safety Authority using the
precautionary approach. They are based on health only and do not take into
account fishery sustainability. For more info on making sound environmental
seafood choices around the world, visit the Marine Stewardship Council’s website