Gamma Linolenic Acid (GLA)
Common names: Gamma linolenic acid also is known as GLA and gamolenic acid.
ÒÒÒ...Positive clinical trials
Safety rating:●...No safety concerns despite wide use.
What is Gamma Linolenic Acid (GLA)?
GLA is found in the seeds and oils of a range of plants including Onagraceae (evening primrose), Saxifragaceae (borage), and Rubaceae (blackcurrant). The richest source of GLA is borage (Borago officinalis).
What is Gamma Linolenic Acid (GLA) used for?Overview
Fatty acids are the basic building blocks for all lipids. They consist of chains of carbon and hydrogen with an end acid group. Fatty acids vary in length and degree of saturation and generally are up to 26 carbons long. The polyunsaturated fatty acids contain more than 1 double bond. The double bonds are at carbon 3 (n-3) or 6 (n-6). GLA falls into the latter family, known as omega-6 fatty acids.
The actual location of the double bond significantly affects metabolism of the fatty acid, such that the structure and function of omega-3 derived eicosanoids differ from those derived from the omega-6 fatty acids (eg, arachidonic acid). For example, omega-3 derived eicosanoids tend to decrease blood clotting and inflammatory responses. This contrasts significantly with the arachidonic acid (omega-6) derived eicosanoids, which increase clotting and inflammatory responses.
Unsaturated fatty acids are essential components of cell membranes and can influence receptors, enzymes, ion channels, and signal transduction pathways. They can influence numerous inflammatory and immunological processes.Traditional/Ethnobotanical uses
The evening primrose plant is native to North America and was introduced into Europe in the 17th century. Native Americans consumed the leaves, roots, and seedpods as food and prepared extracts of the oil for use as a painkiller and asthma treatment. Some of these early therapeutic effects are thought to be because of GLA, which is found in high quantities in the oil.
In the 1930s and 1940s, several investigators found dietary supplementation with essential fatty acids such as GLA to be of therapeutic value in atopic dermatitis (AD). The advent of topical glucocorticoids brought an end to this form of treatment. However, by the early 1980s, there was a return to using these agents because of the unwanted side effects of glucocorticoids, and they have regained scientific interest. Over the last 2 decades, numerous other indications have been proposed for GLA.Rheumatoid arthritis
Clinical studies using GLA (evening primrose oil, borage seed oil, blackcurrant seed oil) suggest a potential relief of pain, morning stiffness, and joint tenderness in rheumatoid arthritis sufferers. Benefits appeared to be increased when dosages were greater than 1.4 g/day of GLA, and administered for at least 6 months.Cardiovascular protection
The apparent low death rate from coronary heart disease among Eskimos has focused interest on the potential benefits of the n-3 polyunsaturated fatty acids. A small clinical study showed benefits in lowering total cholesterol and LDL, and raising HDL cholesterol. These effects suggest that GLA may contribute to cardiovascular protection. However, this is still an area of controversy.Diabetes mellitus
GLA has been studied as for its possible benefits for diabetic neuropathy. Diabetic patients have abnormalities of essential fatty acid metabolism, and therefore require higher amounts of essential fatty acids. Studies have shown that the development of cataracts, retinopathy, and cardiovascular damage can all be slowed by the administration of large daily doses of essential fatty acid. Clinical studies have demonstrated consistent and progressive improvement of neuropathies when treated with GLA.Atopic diseases/Asthma/Psoriasis
GLA has been shown in clinical studies to reduce itching, redness, and toughness of atopic skin. GLA also reduces the inflammation and overall severity of atopic dermatitis, while atopic disease in children often presents as bronchial asthma later in life. However, there have been no animal or clinical studies regarding the use of GLA for atopic bronchial asthma. Although psoriasis does not have an atopic component, the use of GLA has been investigated clinically with inconsistent results.Other uses
GLA supplementation has been shown to increase lymphocytes, a key component in immune response. It also has been proposed that GLA may play important roles in cancer treatment. Small clinical studies have shown some improvement in immunologic status with estrogen-sensitive breast cancer and bladder cancer. Clinical studies have shown that GLA is effective in relieving PMS symptoms, including breast pain.
What is the dosage of Gamma Linolenic Acid (GLA)?
GLA has been studied clinically for a wide variety of conditions, including asthma, dermatitis, and arthritis. Oral doses in trials have ranged from as little as 0.5 to 3 g per day.
Is Gamma Linolenic Acid (GLA) safe?Contraindications
Contraindications have not yet been identified.Pregnancy/nursing
Not to be used by pregnant women and nursing mothers unless recommended by a physician.Interactions
None well documented.Side Effects
No serious adverse effects have been noted.Toxicities
Research reveals little or no information regarding toxicology with the use of this product.
- Little C, Parsons T. Herbal therapy for treating rheumatoid arthritis. Cochrane Database Syst Rev. 2001;CD002948.
- Surette ME, Koumenis IL, Edens MB, et al. Inhibition of leukotriene biosynthesis by a novel dietary fatty acid formulation in patients with atopic asthma: a randomized, placebo-controlled, parallel-group, prospective trial. Clin Ther. 2003;25:972-979.
- Barabino S, Rolando M, Camicione P, et al. Systemic linoleic and gamma-linolenic acid therapy in dry eye syndrome with an inflammatory component. Cornea. 2003;;22:97-101.
- Middleton SJ, Naylor S, Woolner J, Hunter JO. A double-blind, randomized, placebo-controlled trial of essential fatty acid supplementation in the maintenance of remission of ulcerative colitis. Aliment Pharmacol Ther. 2002;16:1131-1135.
- Thies F, Nebe-von-Caron G, Powell JR, Yaqoob P, Newsholme EA, Calder PC. Dietary supplementation with γ-linolenic acid or fish oil decreases T lymphocyte proliferation in healthy older humans. J Nutr. 2001;131:1918-1927.
- Andreassi M, Forleo P, Di Lorio A, Masci S, Abate G, Amerio P. Efficacy of γ-linolenic acid in the treatment of patients with atopic dermatitis. J Int Med Res. 1997;25:266-274.
- Borrek S, Hildebrandt A, Forster J. Gamma-linolenic-acid-rich borage seed oil capsules in children with atopic dermatitis. A placebo-controlled double-blind study. [in German] Klin Padiatr. 1997;209:100-104.
- Zurier RB, Rossetti RG, Jacobson EW, et al. gamma-Linolenic acid treatment of rheumatoid arthritis. A randomized, placebo-controlled trial. Arthritis Rheum. 1996;39:1808-1817.
- Chenoy R, Hussain S, Tayob Y, O'brian PM, Moss MY, Morse PF. Effect of oral gamolenic acid from evening primrose oil on menopausal flushing. BMJ. 1994;308:501-503.
- Nemecz G. Evening primrose. US Pharm. 1998;23:85-94.
- Kerscher MJ, Korting HC. Treatment of atopic eczema with evening primrose oil: rationale and clinical results. Clin Investig. 1992;70:167-171.
- Leichsenring M, Kochsiek U, Paul K. (n-6)-Fatty acids in plasma lipids of children with atopic bronchial asthma. Pediatr Allergy Immunol. 1995;6:209-212.
- Worm M, Henz BM. Novel unconventional therapeutic approaches to atopic eczema. Dermatology. 2000;201:191-195.
- Melnik B, Plewig G. Atopic dermatitis and disturbances of essential fatty acid and prostaglandin E metabolism. J Am Acad Dermatol. 1991;25(5 pt 1):859-860.
- Biagi PL, Bordoni A, Hrelia S, et al. The effect of gamma-linolenic acid on clinical status, red cell fatty acid composition and membrane microviscosity in infants with atopic dermatitis. Drugs Exp Clin Res. 1994;20:77-84.
- Fiocchi A, Sala M, Signoroni P, Banderali G, Agostoni C, Riva E. The efficacy and safety of gamma-linolenic acid in the treatment of infantile atopic dermatitis. J Int Med Res. 1994;22:24-32.
- Kankaanpää P, Nurmela K, Erkkilä A, et al. Polyunsaturated fatty acids in maternal diet, breast milk, and serum lipid fatty acids of infants in relation to atopy. Allergy. 2001;56:633-638.
- Cant A, Shay J, Horrobin DF. The effect of maternal supplementation with linoleic and γ-linolenic acids on the fat composition and content of human milk: a placebo-controlled trial. J Nutr Sci Vitaminol. 1991;37:573-579.
- Wright S, Bolton C. Breast milk fatty acids in mothers of children with atopic eczema. Br J Nutr. 1989;62:693-697.
- Kragballe K. Dietary supplementation with a combination of n-3 and n-6 fatty acids (super gamma-oil marine) improves psoriasis. Acta Derm Venereol. 1989;69:265-268.
- Van Aswegen CH, Du Plessis DJ. Can linoleic acid and gamma-linolenic acid be important in cancer treatment? Med Hypotheses. 1994;43:415-417.
- Das UN. Gamma-linolenic acid, arachidonic acid, and eicosapentaenoic acid as potential anticancer drugs. Nutrition. 1990;6:429-434.
- Solomon LZ, Jennings AM, Foley SJ, Birch BR, Cooper AJ. Bladder cancer recurrence by implantation of exfoliated cells: is γ-linolenic acid an effective tumoricidal agent? Br J Urol. 1998;82:122-126.
- Kenny FS, Gee JM, Nicholson RI, et al. Effect of dietary GLA +/- tamoxifen on the growth, ER expression and fatty acid profile of ER positive human breast cancer xenografts. Int J Cancer. 2001;92:342-347.
- Falconer JS, Fearon KC, Ross JA, Carter DC. Polyunsaturated fatty acids in the treatment of weight-losing patients with pancreatic cancer. World Rev Nutr Diet. 1994;76:74-76.
- Kenny FS, Pinder SE, Ellis IO, et al. Gamma linolenic acid with tamoxifen as primary therapy in breast cancer. Int J Cancer. 2000;85:643-648.
- Das UN, Prasad VV, Reddy DR. Local application of γ-linolenic acid in the treatment of human gliomas. Cancer Lett. 1995;94:147-155.
- Guivernau M, Meza N, Barja P, Roman O. Clinical and experimental study on the long-term effect of dietary gamma-linolenic acid on plasma lipids, platelet aggregation, thromboxane formation, and prostacyclin production. Prostaglandins Leukot Essent Fatty Acids. 1994;51:311-316.
- Horrobin DF. Nutritional and medical importance of gamma-linolenic acid. Prog Lipid Res. 1992;31:163-194.
- Jamal GA, Carmichael H. The effect of γ-linolenic acid on human diabetic peripheral neuropathy: a double-blind placebo-controlled trial. Diabet Med. 1990;7:319-323.
- Keen H, Payan J, Allawi J, et al. Treatment of diabetic neuropathy with γ-linolenic acid. The γ-Linolenic Acid Multi-Center Trial Group. Diabetes Care. 1993;16:8-15.
- Leng GC, Price JF, Jepson RG. Lipid-lowering for lower limb atherosclerosis. Cochrane Database Syst Rev. 2000:CD000123.
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