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Eat fish! Which Fish? That Fish! Go Fish!
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Matthew Picklo

For a healthy heart, the American Heart Association and the Dietary Guidelines for Americans recommends eating two, 3.5 oz servings of fish per week. Questions like "Why? Which fish?" immediately come to mind.  Also,  "Should I be concerned about mercury? Is wild-caught fish better than farmed?"

Why eat fish? Several studies have shown that eating fish reduces risk of heart disease. Fish is an excellent source of protein and many species  are also rich in omega-3 fatty acids, particularly the long chain omega-3's EPA and DHA.  Consuming these long chain omega 3's reduces blood clots, triglycerides and arrhythmias (irregular heartbeats). Eating at least 250 mg of these omega 3's per day is enough to provide health benefits.  Unfortunately, Americans eat less than half of this amount.

But which fish should I eat? Does it matter how I cook it? For a heart-healthy effect, guidelines recommend eating "fatty" or "oily" fish. These terms are misleading, as most of the fish we eat are fairly lean. "Oily" fish like tuna and salmon are typically high in EPA and DHA--lower amounts of which are found in  trout, sardines, walleye, oysters, shrimp and mussels.  Americans consume about 4 lbs of shrimp and 2 lbs tuna and salmon per person each year.  Baking or grilling is recommended instead of frying.

A common concern about eating fish, especially for pregnant and nursing mothers, is mercury. Mercury is a fat-soluble element that  can accumulate particularly in older, large predatory fish like shark, swordfish, king mackerel and tilefish. The US Environmental Protection Agency and the Food and Drug Administration recommend  that women who may become pregnant or are pregnant or nursing, as well as young children limit their intakes to  12 ounces of such fish  as canned tuna or salmon, and should avoid species such as shark and king mackerel. This limit  is well above the two, 3.5 oz servings per week for heart benefits.

As the world's population grows, the demand for fish is increasing. Already, 90 percent of the global wild fish stocks are rated as fully or over-exploited.  For this reason, fish farming, which started in the US in the 1800's, is an increasingly important source of Atlantic salmon.  Farmed in cold water currents, over 1.5 million tons of Atlantic salmon are produced yearly from Norway, Chile, the United States and Canada.  Shrimp, oyster, and mussels, and non-marine fish like rainbow trout and catfish are also extensively produced by such aquaculture methods.

 USDA scientists are studying ways to lower the cost of farming fish while improving omega 3 content and fillet quality.  Nutritionists at the USDA Grand Forks Human Nutrition Research Center recently showed that eating even 4 ounces of farmed Atlantic salmon twice a week raises omega 3s to levels associated with reduced heart disease risk.  What does this research mean for us and our families? Farm raised salmon is a good source of lean protein, and heart-healthy EPA and DHA.

To find out the nutrients in different fish or create a personal eating plan, the USDA provides a free interactive tool called SuperTracker at: Under the Food-A-Pedia tab, you can find the nutrients (including vitamins, minerals, EPA and DHA) and calorie for your favorite fish and seafoods prepared several ways.