- With Mayo Clinic nutritionist
Katherine Zeratsky, R.D., L.D.
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Katherine Zeratsky, R.D., L.D.
Katherine Zeratsky, R.D., L.D.
As a specialty editor for the Food & Nutrition Center, Katherine Zeratsky helps you sort through the facts and figures, the fads and the hype to learn more about nutrition and diet.
A Marinette, Wis., native, she is certified in dietetics by the state of Minnesota and the American Dietetic Association. She has been with Mayo Clinic since 1999.
She is active in nutrition-related curriculum and course development in pediatrics at Mayo Clinic Rochester and nutrition education related to the physiology and recommended intakes for premature infants.
Other areas of interest include breast milk and formula safety, neonatal feeding, and nutrition for breast-feeding mothers.
She graduated from the University of Wisconsin-Madison, served a dietetic internship at the University of Iowa Hospitals and Clinics, and worked as a registered dietitian and health risk counselor at ThedaCare of Appleton, Wis., before joining the Mayo Clinic staff.
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Healthy cooking (8)
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Healthy menus and shopping strategies (7)
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Question
Ground flaxseed: Better than whole?
Does ground flaxseed have more health benefits than whole flaxseed?
Answer
from Katherine Zeratsky, R.D., L.D.
Most nutrition experts recommend ground flaxseed because your body is better able to digest it. Whole flaxseed may pass through your intestine undigested, which means you won't get all the health benefits.
Flaxseed is high in fiber, omega-3 fatty acids and phytochemicals called lignans. Flaxseed is commonly used as a laxative (to improve digestive health or relieve constipation). Both flaxseed and flaxseed oil have been used to help reduce total blood cholesterol and low-density lipoprotein (LDL, or "bad") cholesterol levels and, as a result, may help reduce the risk of heart disease. Although flaxseed oil also contains omega-3 fatty acids, it doesn't have the beneficial fiber that the seeds have.
You can purchase raw flaxseed in bulk — whole or ground — at many grocery stores and health food stores. Whole seeds can be ground in a coffee grinder and then stored in an airtight container for several months. Refrigerating whole seeds may also extend their freshness.
Although the Institute of Medicine has not set a recommended daily intake for omega-3 fatty acids, it has established adequate intake amounts of between 1.1 and 1.6 grams a day for adults. One tablespoon of ground flaxseed provides 1.6 grams of omega-3 fatty acids.
Tips for including flaxseed in your diet:
- Add a tablespoon of ground flaxseed to your hot or cold breakfast cereal.
- Add a teaspoon of ground flaxseed to mayonnaise or mustard when making a sandwich.
- Mix a tablespoon of ground flaxseed into an 8-ounce container of yogurt.
- Bake ground flaxseed into cookies, muffins, breads and other baked goods.
Eye vitamins: Can they prevent or treat glaucoma?
- Dietary Reference Intakes: Macronutrients. Institute of Medicine, Food and Nutrition Board. http://www.iom.edu/Global/News%20Announcements/~/media/C5CD2DD7840544979A549EC47E56A02B.ashx. Accessed Dec. 3, 2009.
- USDA National Nutrient Database for Standard Reference, Release 22. U.S. Department of Agriculture. http://www.nal.usda.gov/fnic/foodcomp/search. Accessed Dec. 3, 2009.
- Flaxseed and flaxseed oil. National Center for Complementary and Alternative Medicine. http://nccam.nih.gov/health/flaxseed/. Accessed Dec. 3, 2009.
- Flaxseed reduces some risk factors of cardiovascular disease. National Center for Complementary and Alternative Medicine. http://nccam.nih.gov/research/results/spotlight/062308.htm. Accessed Dec. 3, 2009.
- Zeratsky KA (expert opinion). Mayo Clinic, Rochester, Minn. Dec. 3, 2009.
