When it comes to eating fish, many of us have been feeling lost at sea lately.

On one hand, nutritionists extol the heart-healthy benefits of fish. On the other hand, the Environmental Working Group (EWG) and the Food and Drug Administration (FDA) have been issuing scary warnings about high levels of mercury in fish.

• Omega-3s are a key ingredient of cell membranes throughout the body, according to Walter Willett, a nutrition expert at the Harvard School of Public Health.
• Scientists have learned that omega-3s help prevent erratic heart rhythms. These omega-3 fatty acids can help stabilize the rhythm of your heart, reducing sudden cardiac death by 50-80% in some studies.
• The fatty acids in fish also make blood less likely to clot inside arteries (which is the ultimate cause of most heart attacks). Also by reducing inflammation, these substances play a role in preventing cholesterol from clogging arteries.
• Omega-3s improve the ratio of good cholesterol (HDL) to bad cholesterol (LDL) and lower triglycerides
• Studies have shown that omega-3s in the diet can help prevent heart attacks, cancer, macular degeneration (age-related blindness) and sudden cardiac deaths.
• Recent studies suggest that omega-3s may protect against breast cancer, prevent flare-ups of arthritis, curb menstrual symptoms, and prolong pregnancy, resulting in higher birthweight babies.
• Getting plenty of omega-3 fatty acids is important at any age, but it may be especially important to women who are pregnant or hoping to be pregnant. "From conception onward, a developing child needs a steady stream of omega-3s, especially DHA (Docosahexaenoic Acid), to form the brain and other parts of the nervous system," according to Walter Willett, author of the "Harvard Medical School Guide to Healthy Eating".

Unfortunately, of course, that's the very population now being warned to avoid many popular kinds of fish because the mercury they contain may damage nerve and brain cells.

Due to the natural release of mercury from the earth's crust as well as human activities like the burning of fossil fuels, our nation's waters are polluted by this toxic heavy metal. Many of the chemicals, pollutants, and pesticides used on land leach into the lakes, rivers, streams, and coastal waters where they are ingested by simple forms of marine life. These life forms, in turn, are consumed by medium-sized fish, which then are consumed by larger fish. Each step of this food chain further concentrates chemical contaminants in fish tissues.

Among the chemicals of biggest concern is mercury. Fish absorb mercury when they feed on smaller aquatic organisms - and we absorb mercury when we eat fish. The accumulation of mercury in the body and brain has been linked to an increased risk for nerve damage, birth defects, psychomotor retardation, and even cerebral palsy, especially in children whose mothers consumed large amounts of mercury-contaminated fish or grain during pregnancy. Scientific evidence confirms that even low doses of methylmercury can cause irreversible damage to the developing nervous system. Babies born with high levels of exposure have had severe disabilities, including mental retardation, seizure disorders, cerebral palsy, blindness, and deafness. The Environmental Protection Agency has estimated that eating only 3 ounces of tuna per day would put a woman's fetus at risk for neurological problems.

Almost all fish contain some mercury, but the levels range from less than 0.01 ppm (part per million) to 0.5 ppm for most fish. The FDA's safety limit for mercury in fish is 1 part per million (ppm). It's only in a few species that levels reach the upper limit of 1.0 ppm. These are large predator fish, such as swordfish, shark, king mackerel, tilefish, and large species of tuna that are used mostly for fresh steaks or sushi. The smaller species of tuna typically used for canning, such as skipjack and albacore, have much lower levels of mercury, averaging about 0.17 ppm.

In January 2001, FDA recommended that pregnant women and women of childbearing age who might become pregnant, eat on average 12 oz of fish per week -- but avoid shark, swordfish, king mackerel, and tilefish. The FDA also recommended that nursing mothers and young children avoid these fish.

EWG (Environmental Working Group) claims that FDA limits are too lax, and that many women eat enough tuna and other fish to raise the amount of mercury in their bodies to dangerous levels. They point to a study from the CDC showing that 10% of American women are very close to having enough mercury in their bodies to put their babies at risk, were they to get pregnant. In April, 2001, they issued a report, entitled "Brain Food: What Women Should Know About Mercury Contamination in Fish," The report is based on the examination of 56,000 records of mercury test results in fish from seven federal, state and other government sources. It states that there are other fish that pregnant women and nursing mothers should avoid, including Gulf coast oysters, tuna, sea bass, halibut, marlin, pike, and white croaker. Also, the report says canned tuna, mahi mahi, cod, and pollock should not be eaten more than once a month.

The report further says that there are some fish considered safe for pregnant women, including farm-raised trout and catfish, shrimp, fish sticks, flounder, wild pacific salmon, mid-Atlantic blue crab, and haddock.

To play it safe, the FDA recommends that women of childbearing age eat shark, tuna, and swordfish no more than once a month. Everyone else, including your daughter, should limit those fish to seven ounces a week. Dr. Andrew Weil recommends limiting intake of canned tuna to one 6 oz can per week.

For all other low risk individuals, they should consume 2-to-3 servings of fish per week. A 3-ounce serving of Alaska salmon or herring contains about 2 grams of omega-3 fatty acids, while 3 ounces of sardines has about 1.3 grams. Eat fish which are considered safe. These include shrimp, pollock, salmon, cod, catfish, clams, flatfish, crabs, and scallops. Wild Alaskan salmon is delicious, contains plenty of omega-3s, and is relatively toxin-free. If fresh salmon is not feasible for you, then canned salmon is an acceptable choice. Stay away from farmed salmon, the most common variety sold in supermarkets and fish markets. Farmed salmon is less expensive than wild salmon, but it may be lower in omega-3s and may contain residues of antibiotics and other drugs that fish farmers use to treat diseases in their farming pens. Moreover, salmon farming can be disastrous ecologically, because it takes several pounds of feed fish to produce one pound of farmed salmon, thus further depleting the oceans.

If you don't like fish, good sources of omega-3s include flax seeds, hemp seeds, walnuts, walnut oil, soybeans, and purslane (Portulaca oleracea). You can also boost your consumption of omega-3s by sprinkling freshly ground flax seeds on salads or cereal or snacking on hemp seeds. However, some people may not be able to convert these vegetarian forms of omega-3s to the longer-chain forms that occur in fish, which are the ones the body needs.

Another option is to take high quality fish oil supplement which is prepared through extensive molecular distillation ensuing elimination of heavy metal and other contamination. Small amounts of fish oil provide the health benefits of eating fish without the chemicals.

The fish oil used in Opti-DHA.is the highest quality available and has gone through an extensive molecular distillation process to ensure the best possible product without toxic chemicals. Opti-DHA contains more DHA than EPA.

A landmark study, the GISSI-Prevention Trial, involved over 11,000 people who had already survived myocardial infarction. This was the first large scale trial that showed supplementation of essential fatty acids significantly lowered the risk of death. This trial used a supplement with more DHA than EPA as in Opti-DHA. This is important to note, as most fish oil products contain more EPA than DHA.

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