Flaxseed Supplementation Increases Omega-3 Fat Levels

by | Jan 13, 2009 | 2008, Cardiovascular Health, Omega - 3

Written by Greg Arnold, DC, CSCS.

Known to be “essential in human nutrition” (1), omega-3 fatty acids (O3FA) can bestow a number of health benefits beyond heart health (2).  These benefits include mental health (3), lung health (4), colon health (5), skin health (6), eye health (7), infant brain health (8) and even weight loss (9).  Current recommendations for O3FA intake range from 200-1000 mg per day (10)

While the most commonly known source of omega-3 fats is fish oil, the diminishing fish supply and concerns over mercury toxicity (11) make it necessary to find other food sources of O3FA.  Fortunately, O3FA’s are found in plant forms, including flaxseed, soybeans, nuts such as walnuts and almonds, and leafy vegetables.  The omega-3 fat found in these plant forms is called Alpha Linoleic Acid (ALA) and has been found to benefit heart health (12).  But because the body can only use omega-3 fats in the fish oil form of EPA and DHA, it isn’t well known whether ALA could be converted to EPA efficiently to be used in the body (13).

Now a new study (14) has found that ALA supplementation can increase omega-3 fatty acid blood levels.  In the study, 62 firefighters received either flaxseed oil in amounts of 1.2, 2.4, or 3.6 grams per day, fish oil in amounts of 600 mg or 1.2 grams per day, or placebo (1 gram sunflower oil per day) for 12 weeks.  The firefighters provided blood samples every two weeks to measure O3FA level in the red blood cells.

The fish oil supplementation, as expected, “produced a rapid increase” in DHA levels (113% increase with 1.2 grams/day) in the red blood cells.  Researchers also found the 2.4 and 3.6 grams of flaxseed oil per day “to significantly increase” red blood cells levels of O3FA, increasing EPA blood levels by 31% and 54%, respectively.  What’s more, no differences were seen in levels of inflammatory proteins or lipid levels like triglycerides.

Flax seeds contain 36 % flaxseed oil, and adding two level Tbs flax seed to hot cereals supplies 8 grams per day of flax oil.  Flax is also available in meal form. For the researchers, “The consumption of ALA-enriched supplements for 12 weeks was sufficient to elevate [blood O3FA] content, which shows the effectiveness of ALA conversion” into the red blood cells.  This study is also significant because it showed that “The amounts of ALA required to obtain these effects are amounts that are easily achieved in the general population by dietary modification.”

Source: Barceló-Coblijn, Gwendolyn, et al. “Flaxseed oil and fish-oil capsule consumption alters human red blood cell n–3 fatty acid composition: a multiple-dosing trial comparing 2 sources of n–3 fatty acid.” The American journal of clinical nutrition 88.3 (2008): 801-809.

© 2008 American Society for Nutrition

Posted January 13, 2009.

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  14. Barceló-Coblijn G.   Flaxseed oil and fish-oil capsule consumption alters human red blood cell n–3 fatty acid composition: a multiple-dosing trial comparing 2 sources of n–3 fatty acid.  Am J Clin Nutr 2008 88: 801-809.