The average American diet is seriously deficient in the essential omega 3's, DHA and EPA. Except for certain types of fish, there are very few sources of these vitally important fats.

Unfortunately, as this well-written article in the Guardian spells out quite succinctly, fish supplies around the world are becoming scarcer each year. Even I see it, every year that I go to Maui the fish are becoming far less abundant. And, add to that the fact that much of the fish that is available are grossly contaminated.

Additionally, eating fish before maturity (meaning it has not had time to reproduce) spells disaster for the ecology. Eating fish that is loaded with toxins spells disaster for your health, completely counteracting any of its inherent benefits.

These are both good reasons for limiting your fish intake, and being mindful of the types of fish you do consume.

The World’s Most Perfect Food – Not so Perfect Anymore

The world’s oceans are so polluted with industrial waste that most commercially available fish have become little more than carriers of toxins – especially mercury – which accumulates throughout the fat and tissues of their bodies.

This isn’t surprising, considering some 40 tons of mercury are released in the United States alone, every year, due to burning coal to generate electricity.

The most common contaminants found in fish include:

• Mercury
• PCBs
• Radioactive substances like strontium
• Toxic metals such as cadmium, lead, chromium and arsenic

Smaller fish, such as herring, sardines, and anchovies fare better than larger fish since they don’t have time to accumulate much mercury in their tissues.

The highest concentrations are found in the large carnivorous fish of the ocean, such as:

GotMercury.org is a good website if you’re curious to see just how high your intake of mercury might be. Not only do they have a handy mercury calculator, but they also perform independent testing on various sources of fish.

You also want to be especially cautious of canned tuna if you’re interested in keeping yourself and your children safe from mercury contamination. Independent testing by the Mercury Policy Project found that the average mercury concentration in canned tuna is far over the EPA’s “safe limits.”

For example, they found that:

• A 22 pound toddler who eats just 2 ounces of tuna per week may exceed the EPA’s “virtual safe limit” of mercury by 400 percent
• A 132 pound woman who eats 12 ounces of canned tuna per week could also exceed the EPA’s limit by 400 percent

Farm-Raised Fish is Much like Factory-Farmed Cattle

Contrary to what industry would like you to believe, farmed fish is NOT a healthier option. Not for you, the fish, nor the environment.

Not only do you still have the problem of mercury, but farm-raised fish also has higher levels of PCBs, another poisonous industrial byproduct. Residues in farm-raised fish can be as much as 9 million times the amount found in the water.

See, in order to be profitable, fish farms must raise large quantities of fish in confined areas, and the overcrowding leads to disease and injuries to the fish. The fish are therefore given antibiotics and chemicals for the parasites like sea lice, skin and gill infections and other diseases that commonly affect them.

Making matters worse, these fish are also given drugs and hormones, and sometimes are genetically modified, to accelerate growth and change reproductive behaviors.

Farmed salmon are also given the chemicals canthaxanthin and astaxanthin to turn their flesh pink. Wild salmon eat a diet of shrimp and krill, which contain natural chemicals that make the salmon pink. Farm-raised salmon do not eat a natural diet, so their flesh would be gray if they were not given these additives.

Always remember that the food chain matters. You eat what your food ate. Beef from grass-fed cattle, for example, contains a healthy balance of omega 3 and omega 6 (about 3:1), whereas corn-fed beef from factory farms has the complete opposite composition, containing far more pro-inflammatory omega 6’s than anti-inflammatory omega 3’s (about 20:1!)

So, What’s Your BEST Omega-3 Source?

Unless you have lab results in your hand that verifies the purity of the fish, I recommend you avoid it.

Your safest and most cost effective choice , however, is to take high-quality krill oil on a regular basis.

I used to recommend taking fish oil or cod liver oil (and I still do in some cases), but aside from the problem of overfishing to the point of near extinction and the potential of mercury contamination in the oil, fish oils also have other drawbacks.

Most importantly, fish oil is low in antioxidant content. And, as you increase your intake of omega-3 fats by consuming fish oil, you actually increase your need for even more antioxidant protection.

This happens because fish oil is highly perishable.

You have to have sufficient antioxidants to ensure that the fish oil doesn't oxidize and become rancid inside your body (oxidation leads to the formation of unhealthy free radicals).

This is one of the main reasons I now recommend getting your omega-3 fats from Antarctic krill oil.

It is superior to fish oil because it contains phospholipids, antioxidants ( more than 47 times the levels found in fish oil!), and omega-3’s bonded together in a way that keeps them safe from oxidation, and makes them easily absorbed in your body. So with krill oil, you can ensure that you’re getting these incredibly healthy fats (EPA and DHA) without having to worry about oxidation issues.

Additionally, your risk of getting any mercury contamination is extremely low since krill are so small they don’t have the chance to accumulate toxins before being harvested.

Personally, I now take krill oil every day. I particularly appreciate the fact that the omega-3 is attached to phospholipids that dramatically increase its absorption, especially into brain tissue.

Remember Plant Based Omega-3s Do NOT Work as Well

Plant based omega-3 sources like flax, hemp and chia are high in ALA and are important sources of nutrients as we all need ALA.  However, the key point to remember is that the conversion of ALA to the far more essential EPA and DHA is typically severely impaired by inhibition of delta 6 desaturase.  This is an enzyme that is necessary to produce the longer chain EPA and DHA from ALA.  Elevated insulin levels impair this enzyme and over 80% of the country has elevated insulin levels.  So from that perspective alone it is important to include animal based sources of omega-3 fats.

There are even studies that show ALA from flaxseed can actually increase your risk of cancer.   Personally, I regularly include ALA omega-3 plant based foods, like flax and hemp in my diet, but these are always combined with animal based omega-3 fats.