Unraveling omega 3 fats

Q: I know that omega 3 fat is good for you. But I am confused about all the different types of omega 3 fat. I have read about EPA and DHA, which are found in fish. I have also read about alpha-linolenic acid which I know is found in flaxseed oil.

Is the type of omega 3 fat in flaxseed oil just as good for you as the one in fish oil? Or does it depend on what your health issues are?

A: Those are great questions, but tough to answer without getting into biochemistry and enzyme conversions. Enough to make anyone's eyes glaze over! I am going to try to simplify it here by dividing your question into two columns.

This week we'll talk about the different types of omega 3 fat in flaxseed oil vs. fish oil, and how they relate to each other. Next week, we will talk about how some of the health benefits differ.

Flaxseed oil has a basic type of omega 3 fat known as alpha-linolenic acid. Your body can use it to make two different types of omega 3 fats known as EPA and DHA.

Now let's say you want a shortcut. Instead of your body making the fats yourself, you go to the store and buy them ready-made. That is what buying fish oil is like.

So why would you go to the store and buy the prefabricated EPA and DHA when you could just make them yourself?

First, because EPA and DHA have specific health benefits that may not apply to other types of omega 3 fat. For instance, they can help people with high triglycerides, which is a type of cholesterol. More on that next week. Second, because your body isn't always that good at making EPA and DHA, depending on a variety of factors.

If you are diabetic or drink alcohol, you may not be able to make EPA as well. In fact, the amount of alpha-linolenic acid that can be made into EPA seems to vary between 18 percent to less than 1 percent in research studies.

DHA may be even harder to convert, although the details are still not entirely clear.

So to be sure they are getting enough EPA and DHA, many people just choose to eat cold-water fish or take fish oil. Examples of cold-water fish include salmon, sardines, herring, kipper and mackerel. Shellfish such as oysters, shrimp and scallops contain lesser amounts.

Flaxseed oil also has health benefits that may be different — or even complementary — from those of fish oil. That makes sense because it has a different type of omega 3 fat, alpha-linolenic acid.

Dr. Astrid Pujari is a Seattle M.D. with an additional degree as a medical herbalist; she practices at the Pujari Center and teaches as part of the residency programs at Virginia Mason and Swedish/Cherry Hill hospitals. Send questions to apujari@seattletimes.com for possible use in future columns. All information is intended for education and not a substitute for medical advice. Consult your doctor before following any suggestions given here.