These days, an increasing number of health-conscious consumers are choosing to eat fish for its heart-healthy benefits. The American Heart Association recommends that adults eat fish twice a week to meet their needs for omega-3 fatty acids, but how do you know if the fish you’re eating is beneficial?
There are many factors to consider when choosing which fish to eat, two of which include species (the type of fish, such as halibut, salmon, etc.) and source (where the fish was raised or caught). These aren’t simple decisions when you consider that the nutritional value of fish varies from species to species, and that each source carries a different potential for contamination, nutrition and environmental impact.
There are millions of fish species, but only a handful are popular for eating and even fewer are considered healthy choices. To choose which species to eat, consider first its fatty acid profile. Fish that live in dark, cold waters naturally contain higher levels of Omega-3’s. The fish richest in omega-3s are cold water fatty fish like salmon, rainbow trout, anchovies, sardines, bass, herring, and tuna.
Next, consider the source. There are two categories of sources of fish: farmed or wild. Each method has its own list of pros and cons, which every consumer will have to weigh to make the best decision for his or her own health and priorities.
Fish farming, or aquaculture, means that the fish are raised in floating net pens near the ocean shore. Another name for this method is “ocean raised.”
Pros of Farmed Fish
- Price: Farmed fish are often cheaper and more readily available than wild fish.
- Controlled diet: Some farmed fish can have higher levels of Omega-3 fatty acids than wild fish. This is because fish farmers can better control the diets of the fish they raise—making sure that their fish eat more feed that is converted into Omega-3s than a fish might normally eat in the wild. However, there is really no way for consumers to gauge the amount of Omega-3’s in one piece of fish versus another.
- Ecology: When fish are farmed, there is a lower danger of overfishing (or depleting) the population of wild fish.
Cons of Farmed Fish
- Contamination: Farmed fish usually contain more contaminants. Farmed fish are fed processed pellets, often made from processed anchovies, sardines and other small fish. Unfortunately, the types of fish used to make the pellets are usually caught in the polluted waters closer to shore and are often contaminated with industrial chemicals. As a result, farmed fish tends to have much higher levels of chemical contaminants that may cause cancer, memory problems, and neurobehavioral changes in children. Farmed salmon, for example, has been found to contain seven times more PCBs (polychlorinated biphenyls), dioxins and pesticides than wild salmon. Consumers can reduce the amount of contaminants in farmed salmon by almost half by grilling or broiling it so that the juices drip off, cooking it until the internal temperature reaches 175 degrees Fahrenheit and removing the skin before eating.
- Antibiotics: Besides being prone to industrial contamination, farmed fish are more subject to disease, which spreads quickly throughout the entire pen. Sick fish can escape into surrounding open water and spread disease to wild fish populations. To control disease, farmed fish are often given antibiotics to prevent the whole group from becoming ill. Research has shown that farmed salmon, for example, are administered more antibiotics by weight than any other type of livestock.
- Lower Omega-3’s: While farmed fish can be fed an enhanced diet to increase its Omega-3’s, there is no way for consumers to know whether one piece of fish contains more healthy fats than another. According to research in The American Journal of Clinical Nutrition, farmed salmon contains two or three times fewer Omega-3’s even though it contains more overall fat than wild salmon due to its grain-based diet. The same is is true for other popular farmed fish, such as catfish and tilapia.
Wild fish, in contrast to farmed, live in open waters and eat a natural diet. Fishermen catch wild fish on open waters, their natural habitat.
Pros of Wild Fish
- Flavor: Many people prefer the taste of wild fish. Farmed fish do not have as much room to move as their wild counterparts, which reduces the amount of muscle they can develop and affects texture and taste.
- Appearance: Wild salmon is naturally bright in color due to its food source (krill and other small sea creatures), while farmed salmon is grayish in color and dyes must be added to bring the flesh to an appealing shade.
- Nutrition: Wild fish are usually healthier (higher in Omega-3s) and less contaminated than farmed fish.
Cons of Wild Fish
- Overfishing: Most marine biologists agree that there will not be enough wild-captured fish available to meet the growing demand, and many fisheries do not catch wild fish in a sustainable way. Overfishing can deplete certain species of fish, which affects the ecosystem at large.
- Price: Fresh wild fish is sometimes hard to find and usually more expensive than farmed fish.
- Distance traveled: Unfortunately, not every fish lover lives on the coast or near a fishery. An Alaskan salmon, for example, must be shipped thousands of miles to reach a grocery store near you. The shipping of fish all over the world uses fossil fuels and pollutes the environment.
Although there are established health advantages to eating fatty fish, the risks of contaminants can’t be ignored either. All fish, wild or farmed, must adhere to FDA limits for PCB content and mercury levels, but some fish may measure in just below that cutoff. This content can build up in the body over time and cause problems later. However, many scientists believe that the heart-healthy benefits of consuming fish outweigh the risk, especially for older adults who may have already had a heart attack. But younger consumers, especially woman who may become pregnant and have a lifetime of exposure to these pollutants ahead of them, may wish to limit the amount of farmed fish they eat.
Only you can decide whether the cardiovascular benefits of fish outweigh the possible safety, nutritional or environmental issues associated with the type of fish you eat. If you eat fish regularly, ask about its source when ordering at a restaurant and read labels for origin when shopping at the supermarket.
No matter what type of fish or seafood you choose, SparkPeople Dietitian Becky Hand offers these top 5 tips for adults* to enjoy healthy fish:
- Make seafood a priority. Enjoy fish or seafood at least twice per week.
- Be adventurous. Try various types of seafood that you enjoy.
- Reel in fatty fish such as salmon and trout. These offer the most health benefits. If you enjoy lean fish such as tilapia and catfish, think about adding another serving of fatty fish to your weekly dinner menu to make up for it.
- Don’t skimp on lean fish. They’re healthy, too! Aside from being low in fat and calories, lean fish and shellfish are also loaded with micronutrients that are necessary for good health. For example, tilapia is high in selenium; clams are high in iron; and oysters are high in zinc.
- Prepare fish properly. Use low-fat cooking techniques such as broiling, baking, stir-frying, and sautéing. Avoid fried fish and highly processed fish foods such as fish sticks. Season with herbs, spices, marinades and rubs.
*These fish guidelines apply to adults who are not pregnant or breastfeeding. Seafood guidelines are different for children and women who are pregnant or breastfeeding.
Editor’s Note: For more information on a variety of fish, sushi and seafood, including printable pocket-size reference guides, visit: www.MontereyBayAquarium.org or the Washington State Department of Health.
This article has been reviewed and approved by SparkPeople nutrition expert, Becky Hand, Licensed and Registered Dietitian.
- Nutritional difference between wild-caught and farm-raised fish? (cookingislife.wordpress.com)
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- Don’t be fooled by Atlantic salmon, Alaska wild caught is hands-down better! (nutritionalkitchen.wordpress.com)
- The seas lie empty (guardian.co.uk)
- Innovations make ‘farmed vs. fresh’ fish debate more nuanced (charlotte.news14.com)
- Fish Farming Safety and Humans: The Good, Bad, and Evil (brighthub.com)
- New salmon virus found in farmed salmon: advocate (cbc.ca)
- Prohibit Factory Farming of Fish in U.S. Oceans (forcechange.com)