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A Protein Primer: Part 3 of 4—Fish

By H.K. Jones

This is the third in a four-part series on protein, an essential building block behind muscle growth and human health. Get started with an introduction to protein and poultry in particular in A Protein Primer: Part 1 of 4-Poultry, and then check out Part 2 of 4—Red Meat for information on four-legged sources of protein. The upcoming part 4 will cover vegetarian protein options.

Underwater Eats: High-Protein Goodness
First things first: Fish is fantastic food. Not only is it packed with the oh-so-important heart-healthy Omega-3 fats, it's also a high-quality protein source, low in saturated fat, and loaded with many healthful vitamins and minerals. More good news: With so many types of fish and seafood readily available at the market and at restaurants, you can experiment with a wide variety of tastes and textures and never get bored. It's no wonder that some of the world's healthiest cultures base get much of their protein from fish.

Fear Factor: Chemical Contamination
Sounds great, right? Well, like a lot of good things in life, there's a potential downside. If you've turned on your TV or read a newspaper or magazine in the past several years, you've probably been barraged by reports and warnings from government agencies and environmental groups about mercury contamination and other harmful chemicals found in fish. The simple summary: Man has polluted the waters that fish live in with nasty chemicals. All creatures have some exposure to this contamination, but the higher up the food chain they are, the more concentrated the contamination in their flesh. If you eat this flesh, you eat these chemicals, which can cause serious health problems if consumed in large doses.

Do the Math: Keep Eating Your Fish
Mercury contamination is obviously not good, but if you cut back on eating fish because of fear of contamination, you're doing yourself a disservice. Get past the headlines of many of those fear-inspiring media reports and you'll come across a reassuring fact: For most people, the risk of contamination from eating fish should not be a concern. According to five Harvard University studies published in the American Journal of Preventive Medicine, exaggerated fish-contamination fears could cause consumers to lower their fish consumption and lose the "substantial nutritional benefits" it provides. The Food and Drug Administration (FDA) and the Environmental Protection Agency advise only a small group (women who may become pregnant, pregnant women, nursing mothers, and young children) to avoid fish with high levels of mercury—shark, swordfish, king mackerel, and tilefish—and to limit any kind of fish to no more than two meals a week.

If you're active and fit and need good sources of protein, you should, well, go fish. The latest FDA advisory says that up to 12 ounces of a variety of fish each week is safe to eat for everyone. Considering that each serving should be approximately three to four ounces, the American Heart Association's target of two servings of fish per week is still well below the FDA's safe limit. Below, learn some important tips for picking and preparing fish and shellfish.

What to Look For
When selecting seafood, choose fatty-dark fish (such as salmon, tuna, and bluefish), which provide a good source of the omega-3 fats; light-colored fish (such as orange roughy, snapper, and sole); as well as a variety of shellfish, which are low in fat but high in protein.

When buying whole fish look for moist skin; bright red, moist gills; firm flesh that bounces back when touched; and clear eyes. When buying fillets, steaks or shellfish look for firm flesh, clear color with even coloring, and a moist appearance.

What to Watch Out For
If you have a choice, pick wild fish over farm-raised, as wild fish are less likely to have high levels of harmful chemicals. That said, even farm-raised fish are a healthier source of protein than many other protein sources; when given a choice between sirloin steak, chicken breast, and farm-raised fish, choose the farm-raised fish.

Never buy fish that has anything but a clean, fresh, and non-fishy smell. If possible, always eat seafood on the same day of purchase. In a pinch, fresh fish can be refrigerated for a day or two, and frozen fish may be stored in the freezer for up to six months, but the taste will definitely suffer.

Be careful not to overcook fish. As a general rule, allow 10 minutes of cooking time for every inch of thickness, and be sure to use a healthy cooking method: baking, broiling, roasting, braising, grilling or stir-frying.

Note: This is the third part of a four part series on protein. The final installment of the series will cover vegetarian sources.

About H.K. Jones: H. K. Jones is a registered dietitian, freelance writer, and nutrition professional based in Washington, D.C.