by Suzanne Girard Eberle, MS, RD, RAC member
While most runners don't take to water naturally, you don't want to miss out on one of its many benefits: eating fish. A diet rich in fish reduces your risk for heart disease and it may also help ward off certain types of cancer, inflammatory diseases like rheumatoid arthritis and even depression. Other good news about fish? It's significantly lower in calories than most other protein-rich foods, and the fats it does contain are of the heart-healthy omega-3 variety. Despite recent concerns about the risk from mercury associated with eating fish and shellfish, it's hard to overstate the health benefits of eating more.
Loading Up on Omega-3's
Fish, especially cold-water "fatty" fish, is the main dietary source of the heart-protective omega-3 fatty aids: eicosapentaenoic acid (EPA) and docosahaxaenoic acid (DHA). Omega-3 fats also include the plant derived alpha-linolenic acid which the body converts to EPA and DHA, although not very efficiently. Omega-3 fats improve heart health by lowering triglycerides, reducing blood pressure and stabilizing irregular heartbeats (arrhythmias). Natural blood thinners, omega-3 fats also reduce the "stickiness" of red blood cells, which can lead to blood clots and strokes, and the body converts them into natural anti-inflammatory substances called prostaglandins. DHA, in particular, promotes a healthy nervous system and is critical for nourishing the developing brain of unborn babies and young children.
The American Heart Association feels so strongly about the evidence supporting omega-3 fats, they've issued the following guidelines: If you don't have heart disease: eat a variety of fish (preferably fatty fish) at least twice a week. Also, include vegetable oils, nuts and seeds (i.e., ground flaxseed or flaxseed oil, walnuts, canola and soybean oils) rich in alpha-linolenic acid in your diet. If you have heart disease: consume about 1 gram of EPA and DHA per day, with as much from fatty fish as possible. Consider supplementing with fish oil capsules; consult first with your physician. If you have high triglycerides: consume 2 to 4 grams of EPA and DHA from both fish and fish oil supplements. Consult your physician about supplement dosages.
Nearly all fish and shellfish contain at least traces of mercury. Mercury occurs naturally in the environment and it also can be released via industrial pollution into the air. As it falls from the air, mercury can accumulate in streams and oceans where it is turned into methylmercury in the water. Fish absorb the methylmercury as they feed in these waters, particularly larger fish that have lived longer and had more time to accumulate it.
The agencies issuing advisories, such as the Food and Drug Adminstration (FDA) and the U.S. Environmental Protection Agency, however, concur that the risk from mercury by eating fish and shellfish is not a health concern for most people. In fact, for middle-aged and older men, and women after menopause, the benefits of eating fish far outweigh the risks if you stay within the established guidelines. The simplest approach to minimize any potentially adverse effects due to environmental pollutants is to eat a variety of fish from week to week.
The fish with the highest levels of mercury (about one part per million), such as shark, swordfish, tile fish and king mackerel also tend to be rich sources of omega-3 fatty acids. The FDA recommends limits of up to 7 ounces of these high-mercury fish per week and up to 14 ounces of fish per week that average 0.5 parts per million of mercury, such as fresh or frozen tuna, orange roughy and red snapper. To determine the mercury content of selected fish, visit the U.S. Food and Drug Administration's website: cfsan.fda.gov/~frf/sea-mehg.html.
Fishy Advice for Pregnant Women and Young Children
High levels of mercury could harm an unborn baby or a young child's developing nervous system. Young children, pregnant women (as well as those planning to become pregnant) and nursing moms can receive the benefits of eating fish and shellfish and still be confident they have reduced their exposure to the harmful effects of mercury by following these three recommendations*:
1. Do not eat high-mercury fish: shark, swordfish, king mackerel or tile fish (golden bass or golden snapper).
2. Eat up to 12 ounces (two average meals) a week of a variety of fish and shellfish that are lower in mercury, such as shrimp, canned light tuna, salmon, pollock, and catfish. (Albacore "white" tuna has more mercury than canned light tuna, so of your two meals a week, limit yourself to six ounces or one average meal of albacore tuna per week.)
3. Check local advisories about the safety of fish caught by family and friends in local rivers, lakes and costal areas. If no advice is available, eat up to six ounces per week of fish caught from local water, but don¿t consume any other fish that week.
*Note: Follow the same recommendations for young children, but serve smaller amounts.
Eat more Fish!
Adding the right amounts of fish to your diet and varying the types you consume can give your health a great boost in many ways. Why not try it out just for the halibut?
Speaking of halibut, don't miss our fish recipes.
About the Author: RAC member Suzanne Girard Eberle, MS, RD is a sports dietitian in private practice in Portland, Oregon. Contact Suzanne at firstname.lastname@example.org.