Fish is a nutrient-rich food proven to improve heart health and prized as a primary nutrient source in many cultures. Fish provides protein without the saturated fat and is a good source of omega 3 fatty acids. Fish has become increasingly popular since word got out about the benefits of eating it at least two times a week.
While fish has many health benefits, some studies have questioned the healthiness of farm-raised fish, especially salmon. There’s also concern about dolphins and fish that are killed in the tuna fishing process; their bodies are thrown back into the sea as waste. The popularity of fish has raised concerns about over-fishing and the sustainability of commercial fishing long-term. The quality of fish has diminished, especially those caught closer to shore and those found in lakes and streams, where contaminants foul our water supply.
Choosing the best fish is not just about what kind of health benefits the species has; the way it was raised or caught is also important to the nutritional profile. And if you are concerned about the environment and sustainability, the destruction left in the wake of the fishing boats matters, too. Species, season, diet, life stage, age and location all affect the contaminant level and nutritional profile of fish. There is no standardization for effective comparisons, and very little regulation, measurement or labeling to inform consumers.
Though more Americans are beginning to learn about factory farming concerns with livestock thanks to authors like Michael Pollan and movies like Food, Inc., many of us still know little about the factory farm process for fish. So let’s start by looking at salmon farming and why it raises so many concerns.
Salmon Farming: It’s No Swim Upstream
When we think of salmon, we usually see the image of a salmon swimming upstream to spawn, fighting against all odds to lay eggs before it dies. But instead of jumping upstream or powering through the ocean waters, farm salmon circle lazily in small pens that have been likened by at least one journalist to floating pig farms. Waste and excess feed cover the sea floor beneath the farms, creating bacteria that consume oxygen that is required to sustain life for creatures that dwell on the ocean floor. Copper sulfate is used on the nets to prevent algae build up but leaves toxic sediment on the sea floor. Fish can also escape through the nets, creating environmental concerns; scientists estimate more than a million farmed Atlantic salmon have escaped into the Pacific and it is unclear what effect this will have on the Pacific salmon population over time.
As with land-based livestock, farm-raised salmon are vaccinated against diseases that spread easily in the close quarters of the pens. They are fed more antibiotics by body weight than any other livestock to prevent infection (creating strains of disease-resistant bacteria in both farmed and wild fish). And they are doused in pesticides to get rid of sea lice.
Sea lice exist in the wild as well, but are rampant in the close quarters of a fish farm. Scientists are concerned that wild species that swim by farms will be exposed to sea lice, which can damage or kill the vulnerable young salmon. Net hauls have dropped significantly and fisherman who once supported the farms as a means of ensuring ocean salmon sustainability are becoming concerned.
Farmers say it’s unlikely that they are responsible for a decline in wild salmon because the pesticide emamectin benzoate is only added to feed when sea lice are present. In Canada, the rules state that farmers must stop use of the pesticide 25 days before harvest to keep the fish safe to eat. But it’s unclear how much exposure is really OK and how much remains in the fatty tissue after dosage has stopped.
Farm salmon are fed smaller chopped up fish and pellets of feed laden with pesticides, raising concerns about sustainability for those fish. It takes an average of 2.4 pounds of wild fish to sustain a one-pound farm raised salmon and scientists are concerned that the farming practice is only making sustainability of ocean fishing worse.
To make salmon skins pink, since they don’t eat the typical salmon diet of pink krill, thus absorbing cartenoid, or use their muscles as much as typical salmon would, farm salmon are fed synthetic pigments including canthaxanthin to turn their otherwise dull gray flesh a vivid pink. In Canada, the flesh color options, manufactured by pharmaceutical company Hoffman-LaRoche, are delivered to the farmers so they can pick the exact shade of pink they like.
Canthaxanthin, when taken in a sunless tanning pill, was linked to retinal damage in Europe. It’s banned in England, and the European commission has issued a warning about it, urging the industry to find an alternative. But it remains legal elsewhere, and in the U.S., scientists aren’t focused on it as they put most of their attention into what they deem to be a bigger problem: PCBs and toxic dioxins in the fish.
PCBs, Importation and Mercury
PCBs, or polychlorinated biphenyls, are highly toxic compounds that were banned in the 1970s. They pose serious health risks to children, especially babies and fetuses, who can experience developmental and neurological problems from repeated or prolonged exposure to even small amounts of PCBs. They affect adults as well, especially those with impaired immune systems or insufficient healthy gut flora.
Even though they were banned decades ago, these industrial compounds are very slow to break down and remain present in our environment, especially in sediment at the bottom of streams, lakes, rivers and coastal areas. They can be absorbed by fish and remain in their fatty tissues, building up in humans if contaminated fish is consumed frequently.
While these contaminants are a concern among wild fish, especially any lake or stream fish or those caught close to shore, two major studies have shown that farmed salmon accumulate more of these substances, which are known carcinogens, than wild salmon. The feed appears to be the concern, as it includes higher amounts of ground up sardines, anchovies and other small fish than a wild salmon would consume.
Manmade contaminants make their way into the ocean and are absorbed by fish. Then those fish are consumed in large amounts by the farm salmon, and the contaminants accumulate in the fatty tissue. It is estimated that farm-raised salmon have seven times as many PCBs in their systems as wild salmon. Farm raised salmon have a higher fat content than wild because they don’t move around much as their active wild counterparts, so they have more fatty tissue to absorb contaminants. Unfortunately, the higher fat content is not healthy omega 3 fatty acids; it’s less healthy, pro-inflammatory omega 6 fat.
It’s estimated that 68% of fish consumed in America is imported from another country, where it is often farmed and not always labeled. While the U.S. has no standards for organic seafood, (though Whole Foods says it has instituted its own farm fish standards to ensure healthy safe fish options), the European Union has had them for years. So organic European fish can be a safe choice. But many fish brought in from other countries contains additional chemicals and additives that we would likely not approve of.
The FDA inspects only about 5% of all imported farm fish, so many countries disregard the rules and take a chance, knowing it’s unlikely that they will get caught. Recently, the FDA blocked the sale of three kinds of fish from China because they contained “unapproved” drugs. However, it’s equally concerning that there are many “approved” drugs that could have been used freely and allowed to become part of our food supply.
Mercury is another concern in both wild and farm-raised fish. While we eat fish for good heart health, mercury can actually increase the risk of heart attacks. Recent studies have shown that like PCBs and toxins such as bisphenol-A (BPA), a known endocrine disruptor that comes from plastic pollution in our waters, mercury levels are higher in farm-raised fish than in the wild.
Mercury from industrial pollution enters the water and is converted to methylmercury, a toxin that is consumed by smaller fish. Again, the larger fish consume the smaller fish and take in that toxin. This occurs in the wild as well, however, as we have just seen, the practice of grinding up large amounts of small fish to feed the farm-raised salmon means they eat much more of the small fish than they would in the wild, increasing their ingestion of toxins.
Clearly there are some issues with fish farming. But to be fair, there are issues with wild fishing as well. The same contaminants are present in lakes, streams and rivers, making many fish from those sources no longer safe to eat. Several states have issued advisories on their lake fish. Fish caught close to the coast face the same concerns. While deep-water fish are the least affected by these issues, these fish are often caught through practices like trolling with large nets that result in the accidental death of other species.
So what can we do? Here are some tips for healthier fish consumption.
Making Healthier Fish Choices
Use safe cooking methods to minimize the consumption of skin and fat, where PCBs accumulate. Trim the fish and remove skin and the fat along the backsides and belly and remove the internal organs, lobster tomalley and mustard of crabs, before you cook them. Try grilling and broiling fish, letting the fat drip away while it’s cooking and minimize use of fish drippings. Avoid frying fish as that seals in the contaminants. And if you are smoking fish, fillet and remove the skin prior to the smoking process.
If you, or your children, love tuna fish, minimize the exposure to mercury by choosing light tuna, not albacore, and eat it less often. Because their brains and nervous systems are still developing, children are particularly susceptible to mercury contamination. According to the Environmental Defense Fund, chunk/solid white is a larger tuna that accumulates more mercury, while skipjack, which is in most canned light/chunk light tuna, has about one-third the mercury level as albacore.
But it’s still important to read the label, as some canned light tuna contains yellowfin tuna, which is similar to albacore in mercury levels. Sometimes labeled (but not always) gourmet or “tonno” these should be eaten only in limited amounts by both children and adults. Small kids should limit tuna to a couple meals a month, while older kids can usually have it safely once a week. (If you have a compromised immune system or are pregnant, you may want to avoid tuna completely.)
Generally speaking, deep-water, cold-water fish are the least contaminated. If you are buying salmon, always look for Alaska wild sockeye or red salmon. But decide what matters to you: omega 3 consumption, avoiding PCBs and mercury or sustainable fishing and make choices based on your priorities. Ask questions about fish sources and vote with your wallet. Support the call for improved farm-fishing standards and practices. And most importantly, don’t be a creature of habit when it comes to fish consumption: Choose a variety of fish for your diet to spread the toxin exposure risk. Fish are a wonderful source of healthy fats and protein and eating fish twice a week–despite the toxin exposure risk–for most people is still a good long-term health choice.
Clearing up the Muddy Waters
While choosing the right fish can be confusing, at least one organization has attempted to simplify the process. The Monterrey Bay Aquarium has put together a guide that evaluates fish based on three major criteria: omega 3 levels, the presence of mercury and other toxins and the sustainability or ocean-friendly status of their harvest/capture. It also factors in whether fish are over-fished and caught faster than they can reproduce.
The aquarium worked with the Harvard School of Public Health and the Environmental Defense Fund to create a list of fish that are Eco-best choices, Eco-good choices and Eco-avoids. They also created a super green list of wild and farmed fish that are good for people and the oceans. The aquarium has created a series of pocket guides by region that you can print and carry with you when you go shopping.
The list changes monthly based on new information. The current best of the best list for May 2010 includes: Albacore Tuna (troll or pole caught from the U.S. or British Columbia), Freshwater Coho Salmon (farmed in tanks from the U.S.), mussels (farmed), oysters (farmed), Pacific sardines (wild caught), rainbow trout (farmed) and salmon (wild caught from Alaska).
No system is perfect, and the aquarium’s top choice of tuna that is troll or pole caught may be a good example, since finding that option in a typical store will be quite challenging, if not impossible. In addition, while they recommend albacore tuna, the Environmental Defense Fund recommends you avoid it for tuna fish sandwiches. Despite not being perfect, the list is an attempt to help you make good choices for your body and our planet. Combined with your own common sense and priorities, you will discover the best fish choices for you and your family.
To your wellness and health: your true wealth!
Author: Inger Pols is the Editor of the New England Health Advisory and Author/Creator, Finally Make It Happen, the proven process to get what you want. Get a free special report on The Truth About Sugar: It’s Not All Equal at www.IngerPols.com
Photo Source: Microsoft Clip Art