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Flaxseed Oil

What You Need to Know About Flaxseed Oil


Updated October 24, 2011

Written or reviewed by a board-certified physician. See About.com's Medical Review Board.

Flaxseed oil is a natural substance derived from the seeds of the flax plant (Linum usitatissimum). Often used as a culinary oil, flaxseed oil is said to offer a host of health benefits.

Uses for Flaxseed Oil

Flaxseed oil is high in alpha-linolenic acid (ALA), a type of omega-3 fatty acid. Since ALA has been found to fight inflammation, it's thought that flaxseed oil may aid in the treatment of inflammation-related health conditions, such as osteoarthritis and rheumatoid arthritis.

In addition, proponents claim that flaxseed oil can help treat the following health problems:

Flaxseed is also said to protect against some forms of cancer (including breast cancer and prostate cancer), promote weight loss, and prevent heart disease.

Benefits of Flaxseed Oil

It's too soon to recommend flaxseed oil in the treatment of any health condition, according to the National Institutes of Health (NIH). What's more, the NIH warns that flaxseed oil seems ineffective for lowering cholesterol and managing rheumatoid arthritis.

However, there's some evidence that consuming flaxseed oil may provide some health benefits. For instance, studies suggest that flaxseed oil may help prevent hardening of the arteries (also known as atherosclerosis), keep blood pressure in check, and improve symptoms of dry eye syndrome. Furthermore, some research shows that heart disease patients who increase their dietary intake of ALA may reduce their risk of dying from cardiovascular problems.

Preliminary findings from laboratory research also indicate that flaxseed oil may help protect against breast cancer.

Flaxseed Oil and Omega-3s

After flaxseed oil is consumed, the body converts ALA into eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), two other types of omega-3 fatty acids. Although there's some evidence that ALA may offer certain health benefits, the evidence for the health effects of EPA and DHA is significantly stronger.

What's more, since the body is not highly efficient at converting ALA into EPA and DHA, some medical experts recommend obtaining your omega-3 fatty acids from fish oil (rather than from flaxseed oil). Indeed, research shows that fish oil is likely effective for increasing your defense against heart disease. In addition, fish oil may help reduce your stroke risk, protect against hardening of the arteries, and provide a number of other health benefits.

Flaxseed Oil vs. Whole Flaxseeds

Unlike flaxseed oil, whole flaxseeds contain soluble fiber and lignans (naturally occurring chemicals with estrogen-like effects). While flaxseed oil is available in whole flaxseeds, it's better to opt for pure flaxseed oil or flaxseed oil supplements if you're looking to increase your intake of ALA.

Since whole flaxseeds may pass through your intestine undigested, nutrition experts often recommend grinding flaxseed (in a coffee grinder, for example) before adding it to cereals, smoothies, or other foods.

It's also important to note that the fiber in flaxseed may lower the body's ability to absorb medications that are taken by mouth. Therefore, flaxseed should not be consumed at the same time as any conventional oral medications or other dietary supplements.

Although flaxseeds are generally considered safe, overconsumption may lead to increased bowel movements and/or flatulence.

Where to Find Flaxseed Oil

Available for purchase online, flaxseed oil can be found in most natural-foods stores. In addition, flaxseed oil is sold in many grocery stores and stores specializing in dietary supplements.

How to Use Flaxseed Oil

Flaxseed oil can be used as an ingredient in salad dressings. You can also add flaxseed oil to smoothies, vegetable dishes, and hot cereal.

Is Flaxseed Oil Safe?

Since flaxseed oil may slow blood clotting and lower blood pressure, anyone taking anticoagulant drugs or blood pressure medications should use caution when consuming flaxseed oil.

There's also some evidence that flaxseed oil might increase the chance of premature birth when taken during the second or third trimesters of pregnancy. Therefore, the NIH advise that pregnant women avoid taking flaxseed oil.


Barceló-Coblijn G, Murphy EJ, Othman R, Moghadasian MH, Kashour T, Friel JK. "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 Sep;88(3):801-9.

Duda MK, O'Shea KM, Tintinu A, Xu W, Khairallah RJ, Barrows BR, Chess DJ, Azimzadeh AM, Harris WS, Sharov VG, Sabbah HN, Stanley WC. "Fish oil, but not flaxseed oil, decreases inflammation and prevents pressure overload-induced cardiac dysfunction." Cardiovasc Res. 2009 Feb 1;81(2):319-27.

Dwivedi C, Natarajan K, Matthees DP. "Chemopreventive effects of dietary flaxseed oil on colon tumor development." Nutr Cancer. 2005;51(1):52-8.

Harper CR, Edwards MJ, DeFilippis AP, Jacobson TA. "Flaxseed oil increases the plasma concentrations of cardioprotective (n-3) fatty acids in humans." J Nutr. 2006 Jan;136(1):83-7.

Harper CR, Edwards MC, Jacobson TA. "Flaxseed oil supplementation does not affect plasma lipoprotein concentration or particle size in human subjects." J Nutr. 2006 Nov;136(11):2844-8.

Kaul N, Kreml R, Austria JA, Richard MN, Edel AL, Dibrov E, Hirono S, Zettler ME, Pierce GN. "A comparison of fish oil, flaxseed oil and hempseed oil supplementation on selected parameters of cardiovascular health in healthy volunteers." J Am Coll Nutr. 2008 Feb;27(1):51-8.

Lee P, Prasad K. "Effects of flaxseed oil on serum lipids and atherosclerosis in hypercholesterolemic rabbits." J Cardiovasc Pharmacol Ther. 2003 Sep;8(3):227-35.

National Institutes of Health "Flaxseed oil: MedlinePlus Supplements". September 2011.

Paschos GK, Magkos F, Panagiotakos DB, Votteas V, Zampelas A. "Dietary supplementation with flaxseed oil lowers blood pressure in dyslipidaemic patients." Eur J Clin Nutr. 2007 Oct;61(10):1201-6.

Taylor CG, Noto AD, Stringer DM, Froese S, Malcolmson L. "Dietary milled flaxseed and flaxseed oil improve N-3 fatty acid status and do not affect glycemic control in individuals with well-controlled type 2 diabetes." J Am Coll Nutr. 2010 Feb;29(1):72-80.

Truan JS, Chen JM, Thompson LU. "Flaxseed oil reduces the growth of human breast tumors (MCF-7) at high levels of circulating estrogen." Mol Nutr Food Res. 2010 Oct;54(10):1414-21.

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