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Gamma-linolenic acid

What is GLA?

Gamma linolenic acid (GLA) is an unsaturated omega-6 essential fatty acid that is produced in the human body from linolenic acid, an essential fatty acid found in vegetable oils and egg yolk.

Where does GLA come from?

GLA can be produced in the body from linolenic acid. Apart from this, gamma linolenic acid is found in a wide range of plant oils, including borage oil, blackcurrant oil and evening primrose oil.

Benefits of GLA

GLA is primarily known for its anti-inflammatory properties, which are particularly beneficial for chronic skin conditions such as atopic eczema. Numerous studies have shown that supplementation with GLA has positive effects in reducing the severity of dry and inflamed skin associated with eczema (1-6). Other benefits of GLA include improved nerve function in diabetic neuropathy (7) and relief from dry eye syndrome (8) and rheumatoid arthritis (9, 10). Other conditions for which CLA is recommended include mastalgia, premenstrual syndrome and symptoms of menopause, although the scientific support for this type of use is controversial (11, 12).

Side effects of GLA

GLA has no known side effects. There are also no contraindications or necessary precautions with GLA supplementation.

Recommended intake

GLA is usually supplemented in a dosage range of 100mg to 1500mg per day.

GLA supplements

GLA is most commonly sold as an active ingredient in Evening Primerose Oil or Borage Oil. Sometimes Evening Primerose Oil is combined with fish oil to provide both omega-3 and omega-6 fatty acids in one supplement.

Combination with other supplements

GLA is most often combined with fish oil or other omega-3 fatty acids.

References

  1. Kawamura A, et al. Dietary supplementation of gamma-linolenic acid improves skin parameters in subjects with dry skin and mild atopic dermatitis. J Oleo Sci. 2011;60(12):597-607.
  2. Foster RH, et al. Borage oil in the treatment of atopic dermatitis. Nutrition. 2010;26(7-8):708-718.
  3. Senapati S, et al. Evening primrose oil is effective in atopic dermatitis: a randomized placebo-controlled trial. Indian J Dermatol Venereol Leprol. 2008;74(5):447-452.
  4. Schalin-Karrila M, et al. Evening primrose oil in the treatment of atopic eczema: effect on clinical status, plasma phospholipid fatty acids and circulating blood prostaglandins. Br J Dermatol. 1987;117(1):11-19.
  5. Kanehara S, et al. Clinical effects of undershirts coated with borage oil on children with atopic dermatitis: a double-blind, placebo-controlled clinical trial. J Dermatol. 2007;34(12):811-815.
  6. Morse NL, Clough PM. A meta-analysis of randomized, placebo-controlled clinical trials of Efamol evening primrose oil in atopic eczema. Where do we go from here in light of more recent discoveries? Curr Pharm Biotechnol. 2006;7(6):503-524.
  7. Horrobin DF. Essential fatty acids in the management of impaired nerve function in diabetes. Diabetes. 1997;46(Suppl 2):S90-93.
  8. Barabino S, et al. Systemic linoleic and gamma-linolenic acid therapy in dry eye syndrome with an inflammatory component. Cornea. 2003;22(2):97-101.
  9. Brzeski M, et al. Evening primrose oil in patients with rheumatoid arthritis and side-effects of non-steroidal anti-inflammatory drugs. Br J Rheumatol. 1991;30(5):370-372.
  10. Belch JJ, Hill A. Evening primrose oil and borage oil in rheumatologic conditions. Am J Clin Nutr. 2000;71(1 Suppl):352S-356S.
  11. Stonemetz D. A review of the clinical efficacy of evening primrose. Holist Nurs Pract. 2008 May-Jun;22(3):171-174.
  12. Chenoy R, et al. Effect of oral gamolenic acid from evening primrose oil on menopausal flushing. BMJ. 1994;308(6927):501-503.