Main constituents

  • Omega-3 and omega-6 type essential fatty acids: alpha linoleic acid (ALA), linoleic acid (LA), and phytoestrogens (lignans). 

Major therapeutic interest

Ground Seeds:

  • Decreasing menopause-related vasomotor symptoms, especially hot flashes;
  • Reducing cholesterol levels;
  • Preventing cardiovascular disease.

Flaxseed oil:

  • Reducing cholesterol levels;
  • Preventing cardiovascular disease.

Whole seeds:

  • Relieving chronic constipation. 

Other therapeutic interest / Traditional Use

  • Treating gastritis and enteritis;
  • Treating enteritis caused by overuse of laxatives;
  • Relieving irritable bowel syndrome;
  • Reducing inflammation of the urinary tract;
  • Treating respiratory infections: chronic cough, bronchitis (used externally as a hot, moist poultice *);
  • Relieving local inflammation, especially boils and pustules (used externally as a hot, moist poultice).


  • Breast or ovarian cancer, or if close relatives have been diagnosed with hormone-dependent cancers as the lignans contained in flaxseed are phytoestrogens that can directly spur the growth of estrogen-dependent tumors (whole and ground seeds);
  • Intestinal occlusion (whole and ground seeds);
  • Intestinal diverticula (whole seeds);
  • Pregnancy: increased risk of premature birth (flaxseed oil);
  • Hypertriglyceridemia (high triglyceride levels in the blood) (ground seeds, flaxseed oil);
  • Bleeding disorders (ground seeds, flaxseed oil);
  • Diabetes: Use carefully, with closely monitored blood glucose levels (whole and ground seeds).

Important Notice

  • Avoid taking at the same time as any other oral medication: wait at least two hours before or after ingestion of whole or ground flax seeds;
  • Whole seeds keep well at room temperature, but the essential fatty acids in the oil are very unstable at warm temperatures and subject to oxidation when in contact with air. It is recommended to grind the seeds immediately before use or refrigerate and use them within two weeks of grinding.

Drug Interactions

Suspected interactions

Whole and ground seeds:

  • May decrease the absorption of drugs taken orally and it is recommended to take whole or ground seeds at least two hours before or after taking medication;
  • May increase the effect of insulin and oral antidiabetic drugs (Actos, Diabeta, Diamicron, Avandia, Glucophage, etc.) and requires close supervision in diabetic patients.

Ground seeds and flaxseed oil:

  • May heighten the effect of anticoagulant/antithrombotic drugs (Coumadin, Lovenox, heparin, etc.), antiplatelets (Plavix, Ticlid), as well as salicylic acid derivatives (acetylsalicylic acid or ASA, Aspirin, Entrophen, etc.) and other nonsteroidal anti-inflammatory drugs (NSAIDs) (Voltaren, Ibuprofen [Advil, Motrin], Naprosyn, etc.)

Scientific name

Linum usitatissimum



Parts used

Seeds (whole or ground), flaxseed oil