By now, you’re likely well aware that fish is pretty darn good for you, and you are probably recommending your clients nosh on more of it. Research shows that it helps us fend off heart disease and depression and is even great for your skin and hair. But recent news may have you thinking something smells fishy. Some fish are drowning in toxic chemicals while others are being loved to death. So what’s one to do? Keep eating fish! Loaded with healthy nutrients, fish can play a significant role in most well balanced diets, as long as you know how to reel in the right kind. Here’s the bottom line on the healthy virtues of fish and some of the dangers you should know before casting your line at the grocery store.
Fish is Protein Rich
For centuries, many cultures such as the Inuit tribe have relied on fish as a source of cheap, readily available protein. Just four ounces of salmon delivers 25 grams of very high quality protein. What’s more, fish’s favorable levels of all the essential amino acids makes it especially useful in repairing and building lean body mass.
The Fattier, the Better
When it comes to beef, chicken and pork, you’re told to cut the fat. Well, throw out that advice for fish because the fattier, the better. Fatty cold water fish such as salmon, sardines, herring, trout and mackerel are the only reliable dietary sources of two potent omega-3 fatty acids, eicosapentanoic acid (EPA) and docosohexanoic acid (DHA), which have a broad range of health benefits that include the following:
- Higher intakes of fish oil have been shown to reduce blood triglyceride levels. High blood triglycerides are a greater risk factor for heart disease than elevated cholesterol levels.
- Omega-3 fats are involved in pathways that reduce the production of inflammatory substances. This means that a diet high in EPA and DHA could reduce inflammation-induced muscle pain associated with killer workouts as well as pain associated with arthritis.
- Because DHA is the predominant fat found in the brain, it’s not surprising that studies have found that higher intakes of fish fat are associated with better mood, fewer episodes of depression and improved fetal brain development.
- By altering metabolic pathways and enzyme reactions, it appears that consuming more of these fatty acids can actually promote the burning of body fat.
- By reducing the stickiness of the blood, fish fat can help reduce blood pressure, which in turns reduces the risk of heart disease.
Fish is Nutrient Dense
Even though the omega-3s and protein get all the accolades when it comes to seafood, there’s other stuff under those gills that’ll keep you healthy and out of the doctor’s office. The iron in fish helps carry oxygen to your working muscles. Their B vitamins play a central role in energy metabolism, and the vitamin D found in the fat of fatty fish like salmon is a potential cancer fighter. And consider eating those bones (they are softened during processing) in canned sardines, salmon and mackerel as they are a good source of bone-building calcium. Fish contains the antioxidants vitamin E and selenium, which fight off foreign invaders called free radicals that are known to promote diseases such as diabetes, cancer and arteriosclerosis.
Sadly, however, there are some serious concerns regarding our fish supply. As a result of our haphazard treatment of the environment, many of the fish in our oceans, lakes and rivers are contaminated and, if not contaminated, are being over fished to the point of potential extinction. Fish farming, mercury emissions and intensive commercial fishing are taking a serious toll. A study published in the scientific journal Nature found that 90 percent of the large predatory fishes have disappeared from the planet’s waters since the 1950s. Not only is this bad for the fish, but it’s also devastating for communities that rely on the ocean.
There are also fishing methods such as dredging (bottom trawling) that destroy fish habitat, thereby decreasing the ability of the ocean to produce fish. Catching shrimp in trawl nets can kill up to 10 pounds of other ocean life for each pound of shrimp caught.
The Biggest Threats to Our Fish Supply
- Commercial over fishing
- Destructive, out dated fishing methods
- Environmentally damaging fish farming operations
- Toxins (i.e., mercury, pesticides) released into the environment
- Poor use of rivers (i.e., dams, irrigation)
- Consumers making poor fish choices
The Mercury Problem
Some of the mercury in our ecosystem is released via natural processes such as volcanic eruptions and rock erosion. However, well over half of the mercury released is the result of human activity such as mining, smelting, burning coal, incinerating waste or disposing of products that contain mercury (e.g., thermostats, electrical switches). In fact, due to poor government regulation, mercury in the atmosphere is increasing at a rate of one percent per year. One major concern with mercury is that when it is released in one part of the world, it can end up in another area via natural transportation (i.e., wind).
Once in the marine ecosystem, mercury is transformed to its more toxic form (methyl mercury) by the actions of bacteria. This mercury then “bioaccumulates” through the food chain, so that predatory fish and animals have much higher levels of mercury than simple organisms and plants. For this reason, larger fish and mammals tend to have higher mercury levels than smaller ones. Remember that humans are large mammals, too.
Consumers can reduce their exposure to PCBs by removing the skin and fat from fish before cooking; however, because methylmercury is distributed throughout the muscle, skinning and trimming does not reduce mercury concentrations in fish. Cooking fish also has no impact on the mercury content of fish.
Even somewhat low levels of mercury in the environment may lead to levels of mercury in fish that can pose a real risk to those who consume them. Since mercury can cross the placenta, it can adversely affect the development of the brain and nervous system of the fetus. Pregnant women and women of childbearing age need to be especially aware of their exposure to mercury. About eight percent of women of childbearing age have enough mercury in their blood to put a fetus at risk. Mercury is a potent neurotoxin affecting the brain and nervous system, leading to neurological damage, behavioural problems, learning disabilities, memory loss and kidney failure and, in some cases, death.
In fact, mercury may negate any of the benefits of eating fish. A Finnish study found that a high content of mercury in hair may be a risk factor for acute coronary events and CVD, CHD and all cause mortality in middle-aged eastern Finnish men. The researchers concluded that mercury may limit the protective effects of fish oil (DHA/EPA) on cardiovascular health.
The Fish Farming Problem
There are some fish farming practices such as that associated with mussels and arctic char that do not have a significant impact on the environment, and then there are others such as Atlantic farmed salmon and Asian shrimp farms that are extremely hazardous to Mother Nature. Some of the problems associated with farmed salmon include:
- Potential for escape and the resulting effect on wild populations
- Increased levels of contaminants found in farmed salmon
- Spreading of diseases to wild salmon populations
- Pollution from the extreme amount of waste produced from the pens
- The use of artificial colors to make the salmon a desired pink color
- The use of antibiotics
Many environmentalists believe that the devastating Tsunami that struck South East Asia was made much worse as a result of the destruction of the off-shore mangrove forests to make way for shrimp farms.
So the question remains whether you can eat fish and obtain its health benefits without exposing yourself to dangerous levels of contaminants and/or contribute to the dangerously low levels of a diminishing fish stock. The answer to this question is yes! With a little education, you can make wise fish choices that will not only contribute to your health but will also contribute to the health of our planet.
Three great fish buying resources are www.fishonline.org, www.oceansalive.org and www.seafoodchoices.com. These web sites will help you determine if a fish is safe to eat.
Seafood Shopping List
Use this list to help steer you away from species that are high in toxins or are being over fished.
Green Light Fish
These fish have low toxin levels and are harvested in an environmentally sustainable manner. Examples of these fish include the following:
- Wild Alaskan Salmon (fresh/frozen/canned)
- Oysters (Farmed)
- Catfish (U.S. Farmed)
- Tilapia (U.S. Farmed)
- Trout (Farmed)
- Arctic Char
- Pacific Halibut
- Mussels (Farmed)
- Atlantic Mackerel
- Shrimp (U.S. Farmed)
- Striped Bass (U.S. Farmed)
- Bay Scallops
- Clams (Farmed)
- Caviar (Farmed)
Yellow Light Fish
Limit your consumption to a couple times per month as these fish may have elevated toxins or in danger of being over fished. Examples of these fish include the following:
- Canned Chunk Light Tuna*
- Yellowfin/Albacore Tuna*+
- King/Snow Crabs+
- Pacific Sole+
- King Crab+
- Sea Scallops+
Red Light Fish
When possible, avoid these fish. They have high toxin levels and/or are harvested in environmentally damaging ways. Examples of these fish include the following:
- Farmed Atlantic Salmon*+
- Orange Roughy*+
- Chilean Seabass*+
- Swordfish* (imported)*+
- Bluefin Tuna*+
- Atlantic Cod+
- Imported Shrimp+
- Pacific Rockfish*+
- Atlantic Halibut+
- Red Snapper*+
- King Mackerel*
- Atlantic Sole/Flounder+
- Wild Caviar+
* Fish that are high in contaminants.
+Fish that are being over fished or poorly harvested.
*+ Fish that are high in contaminants and over fished.
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