It is true that healthy plant oils don't contain EPA and DHA, but it's also true that our bodies can make EPA and DHA out of the ALA found in flaxseed oil, evening primrose oil, and borage seed oil.
The question has always been whether the body can make enough EPA and DHA out of plant oils, which are ready made and immediately available from fish oils.
Three things everyone needs to know about EPA and DHA supplements are:
- The EPA/DHA ratio is not especially important except for infants, women who are pregnant, and breastfeeding mothers. They need more DHA, but their bodies make more DHA from healthy plant oils.
- EPA/DHA supplements include fish oil, krill oil, and microalgae. Plant oils, such as flaxseed oil, contain ALA.
- What are EPA and DHA? They are two omega-3 essential fatty acids. EPA is more important for cardiovascular health, but DHA is more important for brain health.
Until about 1990, most plant oils were deodorized, decolorized, and sent through high-temperature refining towers to be combined with nickel and other heavy metals to make a product that looked prettier on the shelf.
These "damaged" plant oils actually weren't enough to enable the body to make the EPA and DHA it needed, and fish oil was a clearly superior nutritional choice.
That isn't to say fish oil did not have its own problems. Before molecular distillation became popular, it was not unusual for fish oil to be extra "fishy," and to cause various kinds of stomach upset, and to go bad during storage.
But the advent of cold-pressed, organic plant oils, protected from light and oxygen during pressing, filtering, bottling, and storage, makes plant oils a viable source of EPA and DHA.
You just need more plant oil than fish oil to get the same amount of EPA and DHA, generally about 5 times more.
This means if you need the EPA and DHA of one capsule of high-quality fish oil, containing at least 600 mg of EPA + DHA per capsule, then you need at least three 1,000 mg capsules of flaxseed oil to give your body the raw materials to make the same amount of EPA and DHA.
If you are comparing low-quality fish oil that contains as little 180 mg of EPA + DHA per capsule, then you can take 1 capsule of flaxseed oil for every capsule of cheap fish oil.
Converting ALA to EPA and DHA
- Women who have not reached menopause convert about 36% of the ALA in a flaxseed oil capsule into DHA and EPA.
- Women who have passed menopause and men convert about 16% of the ALA in flaxseed oil into EPA and a small amount of DHA.
- Women who are no longer of reproductive age and men actually may do better with fish oil, krill oil, or microalgae, although these aren't absolutely essential to health.
If you compare adding flaxseed oil to food with taking a spoon of cod liver oil every morning, just about everyone will agree that the flaxseed oil tastes better. If you compare the capsules, then quality makes a big difference.
Cheap brands of fish oil that contain "marine liquids" are much more likely to cause stomach upset than flaxseed oil capsules. Flaxseed oil capsules taken in excess (more than 30 a day), however, are more likely to cause stomach upset than high-quality, molecularly distilled fish oil.
The simple fact is, either kind of product will get you your EPA and DHA. But if you prefer a natural, whole foods approach, you will probably prefer liquid, cold-pressed, minimally processed flaxseed oil from a bottle, and if you prefer a gulp-'em-down supplement, you will probably prefer fish oil capsules.
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