By Dr. Mercola

Fish has always been the best source for the animal-based omega-3 fats EPA and DHA, but as levels of pollution have increased, this treasure of a food has become less and less viable as a primary source of healthful fats.

For example, the rate of mercury contamination in tuna and other Pacific fish increased 30 percent between 1990 and 2009. About 40 percent of all U.S. exposure to mercury comes from eating contaminated tuna from the Pacific, and roughly 75 percent of all human exposure to mercury in general comes from eating fish.

Still, tuna remains a favorite staple among many Americans. This may soon change, however, once people get wind of the latest food fraud...

As evidence of seafood fraud and widespread contamination grows, along with mounting evidence of the critical importance of omega-3 fats found in fish, finding and using a viable alternative becomes an increasingly pressing issue.

My favorite animal-based omega-3 source is krill oil, which also provides other important immune boosting benefits courtesy of the astaxanthin it contains. Recent research shows fish oil may help protect against skin cancer, and astaxanthin alone is already known to act as an “internal sunscreen.”

Sushi Lovers Beware: Majority of 'White Tuna' is Actually Dangerous Fish Substitute

According to the nonprofit ocean protection group Oceana, nearly 60 percent of the fish labeled "tuna" in the US is not actually tuna... The startling revelation of absolutely massive seafood fraud came to light in February, when Oceana published its 69-page report,¹ which focuses on fraudulent seafood substitution.

Between 2010 and 2012, Oceana conducted one of the largest seafood fraud investigations in the world to date. More than 1,200 seafood samples were collected from 674 retail outlets in 21 states, which were then genetically tested to determine if they were honestly labeled. As it turns out, the vast majority of the fish were not at all what they were claimed to be...

Overall, a full one-third (33 percent) of the fish samples were mislabeled; substituted for cheaper, less desirable and/or more readily available fish varieties. The results showed that:

• Mislabeling was found in 27 of the 46 fish types tested (59 percent)
• 87 percent of fish sold as snapper was actually some other type of fish
• 59 percent of tuna was some other type of fish
• 84 percent of “white tuna” sold in sushi venues was actually escolar, a fish associated with acute and serious digestive effects if you eat just a couple of ounces
• Grouper, halibut, and red snapper were sometimes substituted with king mackerel and tile fish, two types of fish the FDA advises pregnant women and other sensitive groups to avoid due to high mercury content

Seafood Fraud Found Everywhere Across the US

While seafood substitutions was found in every location where samples were collected, some areas were more affected by substitution fraud than others, and certain types of fish sold in certain locations were substituted more often than others. For example:

• In Seattle, Washington, 18 percent of all fish samples were mislabeled, but 100 percent of all snapper samples were substitutions
• In Northern California, seafood substitutions occurred in 38 percent of all samples
• Southern California had the highest mislabeling rate nationwide, with 52 percent of all fish samples being substituted with other types of fish
• In Austin, Texas, 49 percent of all samples were mislabeled and 48 percent of retail outlets visited sold mislabeled seafood
• 100 percent of sushi samples from New York, NY, Austin, TX, and Washington, DC, were mislabeled

According to Oceana,² more than 90 percent of the seafood consumed in the US is imported, yet only one percent of imports are inspected for fraud, which may explain this clearly out-of-control situation:

“Our findings demonstrate that a comprehensive and transparent traceability system – one that tracks fish from boat to plate – must be established at the national level. At the same time, increased inspection and testing of our seafood, specifically for mislabeling, and stronger federal and state enforcement of existing laws combatting fraud are needed to reverse these disturbing trends. Our government has a responsibility to provide more information about the fish sold in the U.S., as seafood fraud harms not only consumers’ wallets, but also every honest vendor and fisherman cheated in the process – to say nothing of the health of our oceans.”

How Can You Avoid Being Scammed When Buying Fish?

So what can you do? Oceana offers the following tips for protecting yourself against rampant seafood fraud:³

• Ask questions. Consumers should ask more questions, including what kind of fish it is, if it is wild or farm raised, and where, when and how it was caught.
• Check the price. If the price is too good to be true, it probably is, and you are likely purchasing a completely different species than what is on the label.
• Purchase the whole fish. When possible, purchase the whole fish, which makes it more difficult to swap one species for another.

If You Choose Wisely, Benefits of a High-Fish Diet Can Still Outweigh the Risks

Besides seafood fraud, where you might not be getting the actual fish you paid for, there’s still the issue of contamination. Truly, with all the problems associated with fish these days, it’s hard to support fish as a healthful food, but there are still exceptions. It does require some vigilance on your part though.

In terms of contamination, the key is to understand which types of fish are the least contaminated. By choosing wisely, the benefits of a diet high in fish can still outweigh the risks — provided you also do your best to ascertain that you’re actually getting the fish you want, and not a substitution... In the video below, I interview Randy Hartnell, founder-president of Vital Choice Wild Seafood and Organics. I'm a huge fan of their sockeye salmon, and beside a fish dinner at a restaurant here or there, Vital Choice salmon is about the only type of fish I eat, for two primary reasons:

1. Reduced risk of contamination: The risk of sockeye accumulating high amounts of mercury and other toxins is reduced because of its short life cycle, which is only about three years. Additionally, bioaccumulation of toxins is also reduced by the fact that it doesn't feed on other, already contaminated, fish.
2. Superior nutritional content: Wild salmon swim around in the wild, eating what nature programmed them to eat. Therefore, their nutritional profile is more complete, with micronutrients, fats, minerals, vitamins, and antioxidants like astaxanthin (which gives salmon its pink, or in the case of sockeye, red-colored, flesh).

   Farmed salmon, for comparison, are fed an artificial diet consisting of grain products like corn and soy (most of which is genetically modified), along with chicken and feather meal, artificial coloring, and synthetic astaxanthin, which is not approved for human consumption, but is permitted to be used in fish feed.

   Nature never intended fish to eat these things, and as a consequence of this radically unnatural diet, the nutritional content of their flesh is also altered, and not for the better. Farmed salmon tastes different than wild-caught, and much of it has to do with the altered fat ratio, which is dramatically different. Farmed salmon contains far more omega-6, courtesy of their grain-based diet.

   The ratio of omega-3 to omega-6 fat of wild salmon is far superior to farmed salmon. Wild salmon typically has 600 to 1,000 percent more omega-3s compared to omega-6s. So whereas farmed salmon has a 1 to 1 ratio of omega-3s and omega-6s — again due to its "junk food" diet — the ratio for wild sockeye salmon is between 6 and 9 to 1. This is important, because if you're trying to improve your omega-3 to omega-6 balance, you simply will not accomplish it with farmed salmon.

Download Interview Transcript

Beware: Mislabeled Salmon is Also Exceedingly Common

Unfortunately, salmon are also often mislabeled, even though salmon was not specifically pinpointed as a frequently mislabeled fish in Oceana’s fraud report. According to Hartnell, other studies have discovered that as much as 70 to 80 percent of the fish marked "wild" were actually farmed. This includes restaurants, where 90-95 percent of salmon is farmed, yet may be mis-listed on the menu as "wild." The following tips that can help you determine whether the salmon is authentically harvested Alaskan fish are:

1. Canned salmon labeled "Alaskan Salmon" is a good bet, as Alaskan salmon is not allowed to be farmed.
2. In restaurants, mislabeled salmon will typically be described as "wild" but not "wild Alaskan." This is because authentic "wild Alaskan" is easier to trace. The term "wild" is more nebulous and therefore more often misused. In many ways it is very similar to the highly abused "natural" designation.
3. Whether you're in a grocery store or a restaurant, ask the seafood clerk or waiter where the fish is from. If it's wild, they will have paid more for it, so they're likely to understand the value proposition. Since it's a selling point, they will know where it came from. If they don't have an answer for you, it's a red flag that it's farmed, or worse... The US Food and Drug Administration is moving forward with approving genetically engineered salmon to be sold, and as you know, GE foods still do not need to be labeled in the US.
4. Avoid Atlantic salmon, as all salmon labeled "Atlantic Salmon" currently comes from fish farms.
5. Sockeye salmon cannot be farmed, so if you find sockeye salmon, it's bound to be wild. You can tell sockeye salmon from other salmon by its color. It's bright red as opposed to pink. The reason again for this bright red color is its superior astaxanthin content. Sockeye salmon has one of the highest concentrations of astaxanthin of any food.

Omega-3 Fats May Help Prevent Skin Cancer, Study Reveals

In related news, results from the first human clinical trial of its kind shows that consuming omega-3 fish oils can help you prevent skin cancer. Indeed, there’s no shortage of evidence that the omega-3’s you’d ideally get from a diet rich in seafood is critical for your health, which is why it’s so important to find a viable alternative in the face of declining fish quality... According to the findings, published in The American Journal of Clinical Nutrition,⁴ regularly consuming fish oils increases immunity to sunlight. As reported by Medical News Today:⁵

“[Fish oils] directly decreases sunlight-induced immunity suppression - called immunosuppression - which affects the body's power to combat skin cancer and infection. The volunteers consumed a 4g dose of omega-3 - approximately one and a half portions of oily fish each day. Then they were exposed to either 8, 15, or 30 minutes of summer midday sun in Manchester using a specific light machine. A number of other participants took a placebo before being exposed to the sunlight machine.

Immunosuppression was shown to be 50 percent lower in the subjects that took the omega-3 and were exposed to 8 and 15 minutes of sunshine compared with the volunteers who did not take the supplement. Little to no impact on those in the 30 minute group was shown.”

Krill Oil — An Even Better Alternative than Fish Oil

I was one of the first to promote krill as an exceptional source of animal based omega-3 dietary fats. Many have, and some still criticize me for recommending krill oil over fish oil, for the lack of studies to back it up, but the bulk of the new emerging studies are actually confirming that krill is the better option.

For example, research has confirmed that krill has the identical fats as fish oil but is a far higher quality source due to astaxanthin protecting the perishable fats, and the phospholipids that massively increase the absorption of the fats. Furthermore, fish oil, just like whole fish, is also prone to contamination with mercury and other heavy metals. Antarctic krill is not subject to this contamination.

In light of the study above, krill oil makes even more sense, as astaxanthin alone has been shown to act as a very effective “internal sunscreen.” So not only are you getting higher quality omega-3 fats, you’re also getting more potent protection against harmful sun rays, which can allow you to more safely optimize your vitamin D levels by exposing large amounts of skin to natural sun light. I believe it puts you in a perfect win-win situation.

Seafood Fraud and Widespread Contamination Makes Omega-3 Supplement More Important

Fish has always been the best source for the animal-based omega-3 fats EPA and DHA, but with increasing pollution levels, fish has become less and less viable as a primary source of healthful fats. Add to that the obnoxious prevalence of seafood fraud, and the picture is bleak indeed. At the same time, research continues to demonstrate the critical importance of omega-3 fats for human health, making finding and using a viable alternative an increasingly pressing issue.

While I don't advocate taking truckloads of supplements, this is an exception. I do recommend most people consider taking a high quality animal-based omega-3 oil, like krill oil.

Quality is of the essence when selecting any supplement and krill oil is no exception. The only kind of krill oil I recommend is from genuine Antarctic krill. Look for a brand that is cold-processed, which preserves its biological benefits. Please make sure that hexane is not used to extract the oil from the krill as some of the most popular krill oils on the market use this dangerous technique. It should also be free of heavy metals, PCBs, dioxins and other contaminants. The krill should also be harvested in compliance with international conservation standards.