Q. Are store-bought pre-ground flaxseeds as nutritionally effective as buying whole seeds and grinding yourself?

A. “Probably not,” says Barry Swanson, Ph.D., a fellow at the Institute of Food Technologists and professor of Food Science and Human Nutrition at Washington State University. (We went straight to a food-tech pro for this answer.) While pre-ground flaxseeds offer similar amounts of protein, total fat, fiber, minerals and vitamins as those you buy whole and grind yourself, they likely contain lower levels of heart-healthy polyunsaturated fats, including omega-3 fatty acids and conjugated linoleic acid (CLA), says Swanson. Pre-ground flaxseed has been exposed to oxygen longer; oxygen causes polyunsaturated fats to break down. (So do heat and light.) Tell-tale sign that this has occurred: an off smell and/or flavor you might call “rancid.”

To retain the polyunsaturated fatty acids, store your flaxseed—whole or ground—in an airtight container in the fridge or freezer. If you do buy pre-ground, be sure your storage container is dark—and not made of metal, which contains minerals that contribute to fat breakdown. Best bet: Buy whole. Grind only what you need. Relish the freshness. (Note: Whole flaxseeds are very hard and will pass through your body undigested if you don’t grind them before sprinkling them on your cereal or salad. A coffee grinder or small food processor does a fabulous job of “freeing” the nutrients of your flax so that you can absorb them.)


I found this to be very helpful, however, I've been grinding my own for a while now. I wasn't aware of all the advantages in grinding them yourself oppossed to buying them pre-ground though. Thank you for getting this information out.


09/21/2010 - 6:03pm

Glad I found your website. I bought raw whole flaxseed because I didn't want the ground meal, but then it was like okay now what. Thank you so much for this valuable information.


01/09/2013 - 6:29pm

I live in the middle of nowhere and our local stores only carry the ground--very frustrating because I know the difference and feel bad for those that don't. I order my organic whole flax seed online and grind what I need as I need it.


02/25/2013 - 12:05pm

i read that flaxseed is beneficial for psoriasis. My sister claims it cured her psoriasis after a year of grinding flaxseed daily,


04/29/2013 - 8:03pm

I found this sight both helpful and informal,
Since I have added flaxseeds to my diet .
Thanks Juana Crawford


11/01/2013 - 6:32pm

I too am so glad to have read this .I just read the article on the 10 most healthiest seeds on earth .I have been looking for ways to help me get my health back from severe weight loss with stomach. I was about to buy the ground seeds not knowing the importance of doing it as you need it. Losing valuable nutrients buying preground. It is so sad that so many people like me have not found the value in eating seeds to boost their nutrient levels in our life. I hope each one that does know this will value this knowledge and share it with their love ones . It can be a life saving answer for many people like me that can't digest animal protein very well and seeds can be very helpful. Ali


01/20/2015 - 3:37pm

I just bought some ground flaxseed meal and was wondering how to keep it fresh so I appreciate this information. Next time, I will plan to buy it whole and grind it myself. Thank you. maf


01/30/2015 - 9:29am

I am thankful for the good advice of purchasing the flexseeds and grind it at home.I am trying these for the first time for my debities.Just pray it work


02/18/2015 - 4:40pm

Just wondering if whole flaxseed can go stale after some period of time on the shelf?


04/16/2015 - 9:58am

I understand that buying whole flax seeds and grinding them myself is much better, nutritionally, than buying pre-ground flax seeds. And I am happy to do that.
However, if I grind them myself, is it still better to use them right away, after grinding, or can I store them in the refrigerator in a dark container for a month? Will the stored ground seeds be as nutritious as if I used them right after grinding? Or do the Omega 3s start breaking down quickly?
Thank you!


04/20/2015 - 8:57am

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