From cayenne pepper cleanses to shake-weights, the health world has seen several trends come and go. But one fad seems to have stood the test of time: flaxseed. Besides its high fiber content, several studies have tentatively linked this omega-3-rich seed to lowered cholesterol and a reduced risk of heart disease. What can we expect from omega-3 fatty acids? Chan EJ, Cho L. Cleveland Clinic journal of medicine, 2009, Jun.;76(4):1939-2869. Meta-analysis of the effects of flaxseed interventions on blood lipids. Pan A, Yu D, Demark-Wahnefried W. The American journal of clinical nutrition, 2009, Jun.;90(2):1938-3207.
Derived from the blue flax flower, flaxseeds are slightly larger and darker than sesame seeds. And, due to their dense fiber content, flaxseeds are perhaps most commonly used to aid with constipation and other digestive issues (kind of like Scrubbing Bubbles for the stomach). The seeds also contain a high concentration of omega-3 fatty acids, which have been shown to help regulate cholesterol levels. Flaxseed and cardiovascular risk factors: results from a double blind, randomized, controlled clinical trial. Bloedon LT, Balikai S, Chittams J. Journal of the American College of Nutrition, 2008, Jul.;27(1):1541-1087. Meta-analysis of the effects of flaxseed interventions on blood lipids. Pan A, Yu D, Demark-Wahnefried W. The American journal of clinical nutrition, 2009, Jun.;90(2):1938-3207. And one recent study found that consuming 3 tablespoons of flaxseed lignans (compounds in the seed also linked to cancer prevention) every day for three months lowered cholesterol by between 10 and 20 percent (though only in male subjects).
But, despite its potential cardiovascular benefits, flaxseed has only been scientifically shown to have a temporary effect on cholesterol, which can quickly wear off if daily consumption stops. Furthermore, while flaxseed oil is marketed as a heart-health supplement, it's the the seed’s lignans—which aren't present in the refined oil—that might actually be more effective at keeping cholesterol in check. A comparison of fish oil, flaxseed oil and hempseed oil supplementation on selected parameters of cardiovascular health in healthy volunteers. Kaul N, Kreml R, Austria JA. Journal of the American College of Nutrition, 2008, Jul.;27(1):1541-1087.
Your Action Plan
While more research is needed to fully understand flaxseed’s effect on cholesterol, its high fiber content and potential link to heart health make it a welcome addition to nearly any daily routine. Just remember: In order to get the maximum benefit, skip the oil and go for the whole or ground seed. Grinding the seeds is a great way to incorporate all the components into those favorite foods and might even help the body digest more of their nutrients.
In order to keep the lignans and omega-3s from oxidizing (which means they can lose their nutritional value), it's best to grind them fresh. Just try sprinkling some fresh-ground flax into a protein shake or morning oatmeal. Your digestive system (and maybe your heart) will thank you.
Originally published July 2011. Updated March 2016.