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North Dakota State University
NDSU Agriculture Communication
7 Morrill Hall, Fargo ND, 58105-5655,
Tel: 701-231-7881, Fax: 701-231-7044


Prairie Fare: Some Facts about Flax

By Julie Garden-Robinson, Food and Nutrition Specialist
NDSU Extension Service, April 12, 2001

In generations past, women soaked flaxseed in water to release the gummy substance from the seed coat and applied it as a setting gel to their hair. As a graduate student I examined the natural coating on flaxseed, but I didn't use it to help curl my straight hair. I studied it as a potential food additive and found that it improved loaf volume and helped delay staling of bread.

Flax has long been the subject of research at North Dakota State University. Located in the northwest corner of the NDSU campus in Fargo, Flax Plot No. 30 is on the National Register of Historic Places. The plot is used for disease testing and has been planted to flax every year since 1893. It is considered by many to be the oldest in the world continuously used for a plant breeding effort. Last year, North Dakota producers raised 475,000 acres of flax, more than 90 percent of the flax raised in the United States.

Flaxseed, also known as linseed, has been studied by nutrition researchers in recent years. Some have called it a "designer food," "nutraceutical" or "functional food" because of its potential health benefits. These small, flat brown or golden seeds are available in many health or natural foods stores. Flaxseed may be eaten whole or ground in a coffee grinder or food processor to produce a meal with a pleasant nut-like flavor. Whole seeds, however, aren't digested very well unless they're baked or otherwise heated. For best quality, whole seeds can be stored at room temperature for about a year.

The nutrient composition of flaxseed varies with the variety, growing season and location. Flaxseed primarily contains protein, fat and dietary fiber. It is an excellent source of alpha-linolenic acid, a type of omega-3 fatty acid that some scientists believe may reduce our risk of stroke or heart disease. Flaxseed oil is available in some stores.

Since flaxseed is high in fat and susceptible to becoming rancid, it's best to grind it as needed for maximum freshness. The ground product also may be refrigerated or frozen. Because flaxseed is approximately one third fat by weight, ground flaxseed can be substituted for shortening at the approximate ratio of three parts ground flaxseed for every one part shortening. If you make substitutions in recipes, expect some texture and consistency changes in the final product, and start small. Ground flaxseed can be substituted for some of the flour in muffins, quick breads or pancakes.

Some scientists have examined compounds in flax known as lignans, which are phytoestrogens (plant estrogens) similar to compounds found in soy products. Lignans may help protect against certain types of cancer (including cancers of the breast and prostate) and heart disease and may reduce symptoms of menopause in some women.

Flaxseed contains dietary fiber that may help control cholesterol levels. In one study, a group of people with slightly elevated cholesterol levels ate six slices of wheat bread a day for four weeks and, for the second four weeks of the study, ate six slices of bread daily containing 30 percent flaxseed. At the end of the flaxseed study, the subjects had lowered their LDL cholesterol ("bad cholesterol") levels by 19 percent and their overall cholesterol level by 6.9 percent, while not affecting their HDL ("good cholesterol") levels.

Other researchers have incorporated 10 to 20 percent flaxseed into the diets of laying hens to change the fat composition of the eggs without adversely affecting the flavor or other properties. These "designer eggs" are high in omega-3 fatty acids and are on the market in some grocery stores.

How much flaxseed is enough -- or too much? If you intend to incorporate flaxseed in your diet, start with a tiny amount in case of potential, but rare, allergic reactions. Most experts have set a safe upper limit of about 25 grams (about 3 tablespoons) per day. Since the outer coating on flaxseed also has a laxative effect, that's another reason to proceed very slowly with perhaps one teaspoon per day. Raw flaxseed contains cyanogenic glucosides, a potential toxin in high doses, so the maximum amount used in research studies has been 50 grams per day.

As with anything, moderation is the key. It's best to consult a physician or other health practitioner before making dietary changes particularly if you're being treated for a medical condition. Don't expect miracles and stop consuming flax if you have any adverse reactions.


Kathie Richardson
NDSU Library
Fargo, ND 58105

Last updated: 09.05.2007

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