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ASKANERD: 5/31/2004

Roger of Goshen, IN asks:

Do fresh water fish have omega3 fatty acids? (like bluegills)

The nerd responds:  My initial suspicion was that they must, but I needed to do some research to be sure.  I did the research and I am glad I did because I learned some interesting facts about Omega 3's and seafood in general.

How the Inuit Fare
  • lower cholesterol
  • reduced blood pressure
  • fewer blood clots and strokes
  • less arthritis

First, a little background on Omega 3's and why people might be interested in eating more of them.  Omega 3 fatty acids are a kind of polyunsaturated fat.  The body derives derives four basic kinds of fat from food: cholesterol, saturated fat, monounsaturated fat, and polyunsaturated fat.  There has been plenty of evidence of cholesterol and saturated fats leading to health problems (heart disease and cancer, in particular), but since the 1970's, there has been evidence to show that the polyunsaturated fats are actually a beneficial type of fat.  This research was begun when scientists began studying the health of the Inuit people in Greenland.  They noticed that even though these people ate almost nothing but fatty foods (whale, seal, and salmon), they did not have the same heart disease and cancer rates like the rest of Western society.  In time, scientists determined that the rich Omega-3 fats in the Inuit diet was actually helping them stave off the health problems that afflicted the rest of the fat-eating world.

When I started looking into how much Omega 3 one could get from certain fish, I began to realize that part of what makes eating fish good for you is that it helps bring a balance.   There is another polyunsaturated fat called Omega 6 that is just as important as Omega 3 to the body.  The only difference is that most people get more of Omega 6 already because it is available in eggs, cereal, poultry, and vegetable oils.  Research seems to show that getting a balance of Omega 3's and Omega 6's are key to getting the benefits of both.  Thus, even if freshwater fish are not as high as marine fish in Omega 3's, it might not be a bad idea to eat them as opposed to just loading on more Omega 6's!

Fish Omega 3's (gm)
Lake Trout 4.6
Atlantic Mackerel 2.6
Chub 2.6
Herring 2.5
Whitefish 1.8
Pink Salmon 1.0
Halibut 0.8
Bass 0.8
Shrimp 0.5
Tuna 0.5
Catfish 0.5
Lobster 0.4
Sunfish (including bluegills) 0.2
Perch 0.2
Swordfish 0.2
Sole 0.1

To the left I have made a list of the fish that are high in Omega 3's.  You will notice that bluegill are towards the bottom of the list, but that shouldn't necessarily dissuade you from eating them.  If you have easy access to bluegill and can eat them a couple of times a week instead of eating, say, and hamburger on white bread, you are getting some Omega 3's, fewer Omega' 6's, and far less cholesterol.  If you actually catch the bluegills yourself, then you get the extra benefit of the exercise and the freshness of the food.  So eating freshwater fish is certainly a good idea.

Preparing Fish

Omega 3's can be destroyed by too much exposure to light, air, and heat.  Thus, the less processing a fish goes through, the more it will maintain its Omega 3's levels.  So once again, catching your own freshwater fish is a good idea.  You also want to be aware of how you cook your fish.  Baking and pan-frying are two good ways to cook fish, but if you deep-fry the fish or overcook it, you will start to break down the Omega 3's.  Don't cook your fish over too high of a heat and don't cook it for too long.  Also, you may want to use Canola oil since it also has Omega 3 acids.  You also want to avoid eating foods with trans-fatty acids with the fish because trans-fatty acids actually work against Omega 3's.  A good way to avoid trans-fatty acids is to see if the product lists partially hydrogenated oil in its ingredients.  If it does list partially-hydrogenated oil, you can bet that product is high in trans-fat.  For more information about avoiding trans-fats, just do an Internet search for "partially hydrogenated."