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Botanical name(s):

Linum usitatissimum. Family: Linaceae

Other name(s):

flax, linseed, lint bells, winterlien

General description

Flaxseed is an annual. It’s grown in temperate and tropical regions. Oil from the seeds is used as an alternative to fish oil. Flaxseed has a nutty flavor. It’s used in bread and bakery products. The seeds from the flaxseed plant are also used to make linseed cakes and in liniments. The stem of the plant is used to make linen thread.

Flaxseed contains the omega-3 fatty acid alpha-linolenic acid. This acid may help prevent and treat hardening of the arteries (atherosclerosis). It may also reduce total blood cholesterol. It may help reduce inflammatory conditions. These include psoriasis, rheumatoid arthritis, eczema, multiple sclerosis, and ulcerative colitis.

Medically valid uses

Flaxseed oil helps prevent atherosclerosis and heart attack. It can be substituted for other vegetable oils when making foods.

Unsubstantiated claims

Please note that this section reports on claims that have not yet been substantiated through studies.

Flaxseed may help treat the following conditions:

  • Bladder inflammation

  • Gastritis

  • Benign prostatic hyperplasia

  • Vaginitis

  • Hot flashes during menopause

  • Rheumatoid arthritis

  • Gallstones

  • High cholesterol

  • Low lipoprotein A (involved in atherosclerosis)

  • Weight loss

  • Asthma

  • Chronic cough

Some theories suggest that flaxseed may be anticarcinogenic. This means it may block estrogen-stimulated breast cancer. It may also have sugar-reducing properties. It may also have antibacterial, antifungal, and antiviral features.

Dosing format

You can take flaxseed as the cracked or coarsely ground seed. Take 1 tablespoon of the whole or bruised seed with 150 milliliters of liquid 2–3 times per day. Or you can take 2–4 tablespoons of milled linseed gruel per day.

For the oil form, use 1/2–1 tablespoon each day. Put it on salads or on vegetables. You can also bake the oil into muffins. Taking the oil with food is important. This is because the food emulsifies the fat. This helps your body absorb the oil better.

Flaxseed oil is used to lower cholesterol. Specifically, it lowers triglycerides. Flaxseed preparation (made from seeds) works as a laxative. It treats constipation, colons damaged by laxative abuse, and irritable colon.

Side effects, toxicity, and interactions

When you take it as directed, flaxseed doesn’t cause side effects. But taking large amounts of it as a laxative without drinking enough fluids can lead to ileus. This is when your bowel doesn’t contract well. It keeps it from being able to move waste.

Women who are pregnant or breastfeeding should talk to their healthcare providers before taking any herbal medicines. Flaxseed can have mild estrogenic effects. This may harm a pregnancy. However, there is no evidence that flaxseed can harm a pregnancy at this time.

You shouldn’t take flaxseed if you have ileus or an esophageal or gastrointestinal stricture. You also shouldn’t take it if you have an acute inflammatory illness of the intestine, stomach, or stomach entrance.

Flaxseed may delay how quickly you absorb other medicines if you take them at the same time.



Online Medical Reviewer: Poulson, Brittany, RD, CDE
Online Medical Reviewer: Wilkins, Joanna, R.D., C.D.
Last Review Date: 8/1/2016