Fishy Fishy Fishy

I’ve been doing a bit of research lately on fish and thought I’d share some insights.  Fish is a great source of protein and it’s one of the few foods that almost all people will agree is good for you – except some vegan extremists – with the caveat that you have to be careful about where the fish comes from and what kind it is.

So, the benefits that are ascribed to fish is that it is high in protein, relatively low in fat (except for a few fatty varieties), and high in Omega-3 fatty acids.  Omega-3 fatty acids are praised by just about everyone.  They are so called “essential fatty acids” because your body can’t create them on its own, but needs at least the building blocks, and even then it is better to have the actual DHA and ALA instead of making your body do the additional work.

The main problem with fish is the toxic contaminants that fish absorb from the water.  This is mainly the pollutant dimethyl mercury, although I’m sure there are others.  Mercury has been linked to cognitive problems, especially when eaten by pregnant or nursing women and young children.  Autism and Alzheimer’s disease have also been linked to mercury ingestion by some.

When it comes to figuring out what kinds of fish are best to eat the two factors I list above (Omega-3 and Mercury) are of prime importance, but a third critical issue is that of whether the given fish is endangered in any way.  There are lots of groups out there monitoring various fish populations and how the fishing industries are overfishing or using good management practices.  A great site to get info on this is stuff is the Monterrey Bay Aquarium’s Seafood Watch.

As for Mercury, the current theory holds that the higher a fish is on the food chain, the more likely a fish will have mercury.  This is because not only does the fish deal with the mercury in the water, but also with the mercury in it’s food supply, and I guess mercury is absorbed and held by other fish much more so than plant or other foods that are not fish.  So, smaller fish generally are better in this regard, with the smallest being the best – sardines, anchovies, and the like.  But the other factor is where the fish comes from, since mercury content differs from location to location.  It’s hard to find an exhaustive and easily digestible (no pun intended) chart of where the most and least contaminated areas are, but the closest thing I found was a fact sheet put out by the EPA which has advisories by state.  Unfortunately this doesn’t cover the large amounts of fish that isn’t caught within a state, but rather in the Atlantic, Pacific, or even foreign countries like Iceland.  I did find this page on Dr. Mercola’s site which references the Environmental working group, but I am not familiar enough with this group to be able to vouch for them, and you always have to take things on Mercola’s site with a grain of salt.

The other facet of the fish industry which I haven’t mentioned yet is the whole distinction between wild-caught fish and farm-raised fish.  The mercury concerns are only for wild-caught fish as fish farms are able to provide water without any contaminants.  The main problem with farm-raised fish, however, is that they generally have much lower levels of Omega-3 fatty acids, thus removing one of their key benefits.  In addition, there are concerns that pollutants find their way into salmon via their food, which is basically ground pellets made up of other fish.  Other concerns relate to the inbreeding that could be creating a genetically inferior fish prone to disease that if allowed to escape to the wild could contaminate the wild fish gene pool.

In some ways it’s a discouraging situation that doesn’t offer a lot of good solutions.  There are fish populations that look to be managed well and free of mercury, such as wild Alaskan salmon, and again, probably sardines and anchovies are ok, but eating any of these more than a couple times a week may not be without some risk.  One way to get around this a little bit is to take a supplement that provides Omega-3 fatty acids.  Flax seed oil is consumed by some, although I’ve heard both plusses and minuses about flax seed, which does not provide the actual essential DHA and ALA but rather the “building blocks” for your body to make it.  Fish oil capsules, while ok in some cases, according to Dr.’s Michael R. and  Mary Dan Eades, authors of various diet and fitness books including Protein Power, it can also go rancid, and there’s no way you will know because the telling stink of rancid oil is shielded by the capsule.  Rancid oil can actually be really bad for you health.  The Eades recommend a fish-oil or cod-liver oil that you take in liquid form with a spoon.  This may sound horrible to some, but they actually now come with flavoring that hides almost all of the fishiness.  The brand the Eades recommend is Carlson’s wich apparently is highly rated and known for it's lack of fishy taste.

There’s a concern that the mercury and other contaminants will even get into this fish oil and with that in mind, this one lab tested 21 different brands of fish oil supplements and found no unsafe levels of various contaminants (mercury, PCB’s, and dioxins), although I can’t tell exactly what they were specifying as safe and unsafe – you need to subscribe in order to see the full report.

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