Answer: At this time it appears the answer is no, at least not in full, unless you ingest very large doses daily. But flax oil may deliver benefits of its own.
It’s not uncommon for people to think they get the same potential health benefits because both flax oil and fish contain omega-3 fatty acids, but there is a difference in their structure and conversion once in the body.
The omega-3 fatty acids from fish oils, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are the essential fatty acids that have been identified to deliver the purported health benefits. And although flax oil can also be converted to EPA and DHA, the process is inefficient. This requires dosages of flax oil to be far greater than normally recommended if one expects the desired positive outcomes from omega-3 ingestion.
Flaxseed, flax oil, certain nuts (walnuts) and oils (canola and soybean) are a rich source of alpha-linolenic acid (ALA), another omega-3 fatty acid. However, past studies have shown that the conversion of ALA to EPA and DHA is inefficient. Very large doses of ALA (> 5 grams) are needed to significantly increase ALA, EPA and DPA (docosapentataenoic acid, a lesser studied omega-3) in the blood.
More recently, researchers tested various doses (1.2, 2.4 and 3.6 g/day) of flax oil against 1.2 g/day of fish oil and placebo in firefighters. As predicted, the fish oil capsules more than doubled blood levels of EPA and DHA while those using the lowest dose of flax oil (1.2 g/d), which is commonly found in flax oil supplements, did not significantly raise EPA or DHA. The higher doses of flax raised blood levels of EPA between 30-40% but no increase was found for DHA. Therefore the effectiveness of flaxseed or flax oil at raising EPA and DHA to beneficial levels remains unclear, particularly at lower doses. Oily fish such as salmon or fish oil capsules are still the best at delivering the well-known benefits of omega-3s.
If fishy burps (quite common in fish oil supplements) are one reason you don’t use fish oil supplements, you may wish to check out our SuperOmega-3. It is enteric coated to eliminate these odious effects.