Flax (Linum Usitatissimum)

Medical Uses

Flaxseed is used for constipation and for intestinal cleansing in diverticulitis. It is also used for menopausal symptoms and sore throats and for its antioxidant effects.

Historical Uses

Flax is one of the earliest foods known to humans. It is also a textile fiber used to make linen. The seed is used in paints (linseed oil). Flax has also been used to make paper.


Flax is cultivated as a crop.

Flax: Part Used

• Seeds

Major Chemical Compounds

• Alpha-linolenic acid

• Lignans

• Fiber

• The best source of omega-3 essential fatty acids

Flax: Clinical Uses

Flaxseed is used for constipation and for intestinal cleansing in diverticulitis. It is also used for menopausal symptoms and sore throats and for its antioxidant effects. It may help to prevent or decrease the risk of cardiovascular disease. Flaxseed is approved by the German Commission E for “chronic constipation, irritable colon, diverticulitis and as mucilage, externally for inflammation”.

Mechanism of Action

Essential fatty acids reduce the risk of blood clotting and thus decrease the risk of heart disease and stroke. They are building blocks of prostaglandins, which help to reduce pain and inflammation; help promote relaxation in stress; and improve the immune system, skin, and digestive system. Lignans are mildly estrogenic.

Flax: Dosage

Flaxseeds: Take 1 tablespoon of fiaxseeds (10 g) up to three times a day with a glass of water (at least 150 mL). Flaxseed can be ground, eaten whole, or soaked in water.

Flaxseed oil: Use flaxseed oil to make salad dressings or take 1 to 2 tablespoons a day.

Poultice: Mix flaxseed flour into a paste with warm water and apply poultice to the inflamed area.

To get the best effects from essential fatty acids, it is important to eat a healthy diet that contains vitamins A, B3, B6, C, and E; beta carotene; magnesium; selenium; and zinc. Store flaxseed oil in a dark bottle in the refrigerator.

Side effects

None are known.


• Bowel obstruction.

Herb-Drug Interactions

Flaxseed may reduce the absorption of other drugs. It should be used cautiously if the patient takes an antidiabetic drug.

Pregnancy and Breast-Feeding

No restrictions are known.

Summary of Studies

deLorgeril et al. (1994). In the Lyon Diet Heart Study, a 5-year French study, investigators looked at patients who had had a myocardial infarction during the 6 months before the study period. Patients substituted flaxseed spread for butter and also limited their intake of saturated fats. Results: Patients who adopted the study protocol were quite successful in reducing a second myocardial infarction and reducing mortality.

Parbtani & Clark (1996). In this study,patients with systemic lupus erythematosus ate a diet that included 30 grams of flaxseeds a day. Results: Patients had improved kidney function and reduced plasma lipids. (Low-density lipoprotein levels declined by 11 percent.)

Prasad (2001). Secoisolariciresinol diglucoside (SDG), an antioxidant from flaxseed, slowed the development of Type 2 diabetes in rats.

Velasquez & Bhathena (2001). In a review article it was shown that eating flaxseed and soy protein reduced proteinuria and preserved renal function in chronic renal disease in rats. It was unclear which active constituent was responsible.

Kettler (2001). This study showed that use of omega- 3 fatty acids, including flaxseeds, may preserve bone density and retard postmenopausal bone loss.

Flax: Warnings

• Don’t take flaxseeds if you have a bowel obstruction.

• If you take any prescription medications, talk with your health-care practitioner before you take flaxseed.

• Don’t use flaxseed if you take a medication for diabetes.


Try adding flaxseed, almonds, and raisins to yogurt, or grind some flaxseed and add it to breads or muffins.

Flaxseed Banana Bread

  • ½ cup light brown sugar
  • 1 egg
  • 3 tablespoons oil
  • 1¼ cup unbleached flour
  • 1 teaspoon baking soda
  • 1 cup mashed bananas
  • ½ cup buttermilk (If you don’t have buttermilk, place 1 tablespoon of vinegar in low-fat milk)
  • ¾ cup ground flaxseed
  • 1 teaspoon baking powder

Preheat oven to 350°F. In a large bowl, combine sugar, buttermilk, egg, and oil, and beat this mixture together. In a separate bowl, combine flour, flaxseed, baking powder, and soda. Mix these ingredients and add to the other ingredients. Stir, but do not over-mix. Pour into greased loaf pan and bake for about 40 minutes. Cool 5 minutes and, while warm, turn the loaf out onto a rack.