Flaxseed

Botanical Name(s):

Linum usitatissimum. Family: Linaceae

Other Name(s):

flax, linseed, lint bells, winterlien

General Description:

Flaxseed is an annual grown in temperate and tropical regions. Oil extracted from the seeds is used as an alternative to fish oil. Flaxseed has a nutty flavor and is 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, which can be potentially beneficial in the prevention and treatment of atherosclerosis and in the reduction of the total blood cholesterol. It may help reduce inflammatory conditions such as psoriasis, rheumatoid arthritis, eczema, multiple sclerosis and ulcerative colitis.

Medically Valid Uses:

Evidence suggests that flaxseed oil is beneficial in preventing atherosclerosis (hardening of the arteries) and heart attack. Flaxseed oil can be substituted for other vegetable oils in the preparation of foods.

Unsubstantiated Claims:

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

Flaxseed is claimed to be helpful in treating bladder inflammation, gastritis, benign prostatic hyperplasia, vaginitis, menopausal hot flashes, rheumatoid arthritis, gallstones, elevated cholesterol levels, decreased lipoprotein A (involved in atherosclerosis), weight loss, asthma and chronic cough.

Some theories suggest that flaxseed may be anticarcinogenic, inhibiting estrogen-stimulated breast cancer. It may also have sugar-reducing and antibacterial/antifungal/antiviral properties.

Dosing Format:

Flaxseed can be taken as the cracked or coarsely ground seed, using one tablespoon of the whole or bruised seed with 150 ml of liquid two to three times a day. It can also be taken as 2 to 4 tablespoons of milled linseed gruel a day. If taken in the oil form, 1/2 to 1 tablespoon can be put in salads or on vegetables each day. The oil is often baked into muffins. Taking flaxseed oil with food is important, as food emulsifies the fat and aids in its absorption.

Flaxseed oil: lipid reducing (lowering triglycerides)

Flaxseed preparation (made from seeds): laxative (for constipation, colons damaged by laxative abuse, irritable colon)

Side Effects, Toxicity and Interactions:

The use of large quantities of flaxseed as a laxative with too little fluid can lead to ileus. However, with proper use there are no other side effects.

Women who are pregnant or breast-feeding should consult a physician before taking any herbal medicines.

You should not take flaxseed if you have ileus, an esophageal or gastrointestinal stricture, or an acute inflammatory illness of the intestine, stomach or stomach entrance.

Flaxseed may delay the absorption of drugs taken simultaneously.

Additional Information:

Click here for a list of reputable Web sites with general information on nutrition.

References:

1. Gruenwald J, Brendler T, Jaenicke C, eds. PDR for Herbal Medicines. Montvale, NJ: Medical Economics Company; 1998.

2. Navarra T, Lipkowitz MA. Encyclopedia of Vitamins, Minerals, and Supplements. New York, NY: Facts on File, Inc.; 1996:81.

3. Miller LG, Murray WJ. Herbal Medicinals. Binghamton, NY: Pharmaceutical Products Press, Haworth Press Inc.; 1998:335.

4. Mantzioris E, James MJ, Gibson RA, et al. Differences exist in the relationships between dietary linoleic and alpha-linolenic acids and their respective long-chain metabolites. Am J Clin Nutr. 1995;61(2):320-324.

5. Thompson LU. Just the flax, ma'am: researchers testing linseed. J Natl Cancer Inst. 1994;86(23):1746-1748.

6. Layne KS, Goh YK, Jumpsen JA, et al. Normal subjects consuming physiological levels of 18:3(n-3) and 20:5(n-3) from flaxseed or fish oils have characteristic differences in plasma lipid and lipoprotein fatty acid levels. J Nutr. 1996;126(9):2130-2140.

7. Turek JJ, Schoehlein IA, Watkins BA, et al. Dietary polyunsaturated fatty acids modulate responses of pigs to Mycoplasma hyopneumoniae infection. J Nutr. 1996;126(6):1541-1548.

8. Caughey GE, Mantzioris E, Gibson RA, et al. The effect on human tumor necrosis factor alpha and interleukin 1 beta production of diets enriched in n-3 fatty acids from vegetable oil or fish oil. Am J Clin Nutr. 1996;63(1):116-122.

9. Nestel PJ, Pomeroy SE, Sasahara T, et al. Arterial compliance in obese subjects is improved with dietary plant n-3 fatty acid from flaxseed oil despite increased LDL oxidizability. Arterioscler Thromb Vasc Biol. 1997;17(6):1163-1170.

10. Harris WS. N-3 fatty acids and serum lipoproteins: human studies. Am J Clin Nutr. 1997;65(5):1645S-1654S.

11. Billman GE, Kang JX, Leaf A. Prevention of sudden cardiac death by dietary pure omega-3 polyunsaturated fatty acids in dogs. Circulation. 1999;99(18):2452-7.

12. Johansen O, Seljeflot I, Hostmark AT, Arnesen H. The effect of supplementation with omega-3 fatty acids on soluble markers of endothelial function in patients with coronary heart disease. Arterioscler Thromb Vasc Biol. 1999;19(7):1681-6.

13. Dietary supplementation with n-3 polyunsaturated fatty acids and vitamin E after myocardial infarction: results of the GISSI-Prevenzione trial. Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto miocardico [see comments]. Lancet. 1999;354(9177):447-55.

14. Grundt H, Nilsen DW, Hetland O, Mansoor MA, Aarsland T, Woie L. Atherothrombogenic risk modulation by n-3 fatty acids was not associated with changes in homocysteine in subjects with combined hyperlipidaemia. Thromb Haemost. 1999;81(4):561-5.

15. von Schacky C, Angerer P, Kothny W, Theisen K, Mudra H. The effect of dietary omega-3 fatty acids on coronary atherosclerosis. A randomized, double-blind, placebo-controlled trial. Ann Intern Med. 1999;130(7):554-62.

16. Prasad K, Mantha SV, Muir AD, Westcott ND. Reduction of hypercholesterolemic atherosclerosis by CDC-flaxseed with very low alpha-linolenic acid. Atherosclerosis. 1998;136(2):367-75.

17. Rustan AC, Nenseter MS, Drevon CA. Omega-3 and omega-6 fatty acids in the insulin resistance syndrome. Lipid and lipoprotein metabolism and atherosclerosis. Ann N Y Acad Sci. 1997;827:310-26.

18. Prasad K. Dietary flax seed in prevention of hypercholesterolemic atherosclerosis. Atherosclerosis. 1997;132(1):69-76.