Gamma-Linolenic Acid (GLA)


Gamma-linolenic acid (GLA) is an essential, “good” fat. It has been used to lower blood pressure, ease diabetes symptoms, and reduce swelling in joints. GLA can be taken as a pill or powder. It is also found in black currant seed oil, borage oil, and primrose oil.


200 to 500 milligrams daily

What Research Shows

May Be Effective

  • Rheumatoid arthritis —may ease symptoms D1, D2

May Not Be Effective

  • Cardiovascular disease —may not have benefit B1

Not Enough Data to Assess

  • Atopic dermatitis A1, A2
  • Diabetic neuropathy C1

Editorial process and description of evidence categories can be found at EBSCO NAT Editorial Process.

Safety Notes

It is likely safe to take gamma-linolenic acid in small doses for a short time. Not enough studies have been done to say whether it is safe to take for a long period. It is also not known whether it is safe to take by women who are pregnant or breastfeeding.


Talk to your doctor about any supplements or therapy you would like to use. Some can interfere with treatment or make conditions worse.



A. Atopic Dermatitis

A1. van Gool CJ, Thijs C, et al. Gamma linolenic acid supplementation for prophylaxis of atopic dermatitis--a randomized controlled trial in infants at high familial risk. Am J Clin Nutr. 2003 Apr;77(4):943-951.

A2. van Gool CJ, Zeegers MP, et al. Oral essential fatty acid supplementation in atopic dermatitis-a meta-analysis of placebo controlled trials. Br J Dermatol. 2004 Apr;150(4):728-740.

A3. Foolad N, Brezinski EA, et al. Effect of nutrient supplementation on atopic dermatitis in children: a systematic review of probiotics, prebiotics, formula, and fatty acids. JAMA Dermatol. 2013 Mar;149(3):350-355.

B. Cardiovascular Disease

B1. Hooper L, Al-Khudairy L, et al. Omega-6 fats for the primary and secondary prevention of cardiovascular disease. Cochrane Database Syst Rev. 2018 Nov 29;11:CD011094.

C. Diabetic Neuropathy

C1. Keen H, Payan J, et al. Treatment of diabetic neuropathy with gamma-linolenic acid. The gamma-Linolenic Acid Multicenter Trial Group. Diabetes Care. 1993;16(1):8-15.

D. Rheumatoid Arthritis

D1. Leventhal LJ, Boyce EG, et al. Treatment of rheumatoid arthritis with gammalinolenic acid. Ann Intern Med. 1993 Nov 1;119(9):867-873.

D2. Zurier RB, Rossetti RG, et al. gamma-Linolenic acid treatment of rheumatoid arthritis. A randomized, placebo-controlled trial. Arthritis Rheum. 1996 Nov;39(11):1808-1817.

Last reviewed July 2019 by EBSCO NAT Review Board Eric Hurwitz, DC  Last Updated: 5/6/2020