Fish are certainly superfoods.  They are touted for their low-calorie, high protein, low-fat nutritional profiles and the American heart association recommends eating them at a minimum of two times per week.  Additionally, fish are the best natural sources of omega-3 fats.  According to researchers, Omega-3 fats are a type of fat that are very beneficial to the body.  Omega-3 fats have been shown to reduce inflammation, have neurological benefits, and even help to promote healthy hearts.  But, did you know not all fish have the same benefits?  The environment that a fish lives in is a crucial factor in determining just how healthy your fish is.  Specifically, there are two types of fish that we all should pay attention to: wild-caught vs. farm-raised fish.

Wild-caught fish live out their natural lives until they are caught and brought to market.  In the open oceans they feed on smaller fish or algae.  By living in their natural environment they are leaner—in fact they have been shown to have five times less fat than farm raised fish—and have more beneficial compounds that they garner naturally in the food chain.  On the other hand, farm raised fish live out their natural lives in pens were they are fed a mixture of factory-manufactured “chow”.  By eating this chow and not living in natural open waters they become fattier, less healthy, and have a higher ratio of omega-6 fats to omega-3 fats.  Furthermore, research out of the center for genetics, nutrition and health suggests that eating a diet with a low omega-6 to Omega-3 fatty acid ratio has many health benefits.   The journal Biomedicine and Pharamotherapy states that these benefits include a reduced risk of cardiovascular disease and autoimmune diseases, and maybe even a reduced risk of some cancers!

So now that we know that we want to eat wild-caught fish as compared to farm-raised fish, how can we tell the difference?  The first thing to do is to ask!  Fishmongers are very knowledgeable about where their fish come from and many are proud to sell wild-caught fish as compared to farm-raised fish.  If you are buying fish from a cooler in the super-market be sure to read the labels to see where the fish come from.  All wild-caught fish should say, “wild caught” on the label.  Additionally, for salmon there is one more criteria that tells us that a piece of salmon may be farm-raised.  According to the Monterey Bay Aquarium’s Comprehensive Database, Atlantic salmon usually means farm-raised.  If you see Atlantic salmon it is best to avoid it.

Okay, so let’s recap.  When it comes to fish, there are two types we should pay attention to, wild-caught vs. farm-raised fish.  Wild caught fish live natural lives and have a lower omega-6 to omega 3 ratio (this is good because it means more omega threes are available to be used).  Farm raised salmon live unnatural lives, have higher overall fat, and often times have artificial colorants added to them to make them look more palatable.  Farm raised and wild-caught fish are practically two separate foods.  Choose wild-caught fish whenever possible, your body will thank you for it.

This is a guest post by Jeremy Zaks, MD Candidate, Tulane University School of Medicine

References

American Heart Association: Fish and Omega-3 Fatty Acids

 

Mozaffarian, D. Fish Oil and Marine omega-3 Fatty acids. In: UpToDate, Basow, DS (Ed), UpToDate,
Waltham, MA, 2012

Simopoulos, A P P. “The importance of the ratio of omega-6/omega-3 essential fatty acids.” Biomedicine & pharmacotherapy 56.8 (2002): 365-79