Evening primrose oil contains gamma-linolenic acid (GLA), an essential fatty acid in the omega-6 family of oils that is metabolized to dihomogammalinolenic acid (DGLA). These fatty acids are precursors to prostaglandins series 1 and 2 (PGE1 and PGE2).  Evening primrose oil contains about 4 to 16 % GLA while borage oil has about 22% and black currant seed oil has about 17%. EPO has a high concentration of linoleic acid. To buy Evening Primrose Oil supplement.
       
Evening Primrose Oil study
Evening primrose oil has antioxidant and anti-inflammatory properties.
Evening primrose oil has shown inconsistent results in the treatment of atopic dermatitis and other medical conditions.
Neither fish oils or evening primrose oil have been found to be helpful in reducing mastalgia (breast pain).

Evening primrose oil benefit
The whole topic of which oils and in which amounts are ideal for maintaining health and fighting disease is very complicated, but overall, in my opinion, We prefer to use Fish Oils or flax seed, rather than evening primrose oil supplements. However, we may alter our opinion if new research finds evening primrose oil has definite clinical benefits.

Evening Primrose study
Quantitative analysis of anti-inflammatory and radical scavenging triterpenoid esters in evening primrose oil.
Knorr R. Friedrich-Schiller-University Jena, Semmelweisstrasse 10, D-07743 Jena, Germany.
J Agric Food Chem. 2004 Jun 2;52(11):3319-24.
Cold pressed, nonraffinated evening primrose oil was recently found to contain lipophilic triterpenoidal esters with radical scavenging and anti-inflammatory properties. A simple and robust method for the quantitative analysis of these 3-O-trans-caffeoyl derivatives of betulinic, morolic, and oleanolic acid was developed and validated.

Evening primrose oil for breast pain
Evening primrose oil and fish oil for severe chronic mastalgia: a randomized, double-blind, controlled trial.
Blommers J,. rije Universiteit University Medical Center, Amsterdam, The Netherlands.
Am J Obstet Gynecol. 2002 Nov;187(5):1389-94.
The purpose of this study was to evaluate the effect of evening primrose oil and fish oil on breast pain in premenopausal women with severe chronic mastalgia, in a randomized double-blind factorial clinical trial. One hundred twenty women were placed randomly into four groups: (1) fish oil and control oil, (2) evening primrose oil and control oil, (3) fish and evening primrose oils, or (4) both control oils during 6 months. Corn oil and corn oil with wheat germ oil were used as control oils. The change in the percentage of days with breast pain after 6 months of treatment was analyzed on an intention-to-treat basis. The decrease in days with pain was 12 % for evening primrose oil and 13% for its control oil; the decrease in days with pain was 15% for fish oil and 10% for its control oil. All groups showed a decrease in pain. Neither evening primrose oil nor fish oil offered clear benefit over control oils in the treatment of mastalgia.

Effect of evening primrose oil on clinically diagnosed fibroadenomas.
Kollias J. Nottingham City Hospital, Nottingham, UK.
Breast. 2000 Feb;9(1):35-6.
The effects of oil of evening primrose oil on fibroadenomas was assessed over a 6-month period. Eleven out of 21 (52%) of fibroadenomas receiving evening primrose oil and 8 out of 19 (42%) controls reduced in size. This study demonstrates that evening primrose oil does not significantly effect the natural history of breast fibroadenomas.

Evening primrose oil supplement inquiries
Q. I notice that when I take 1300 mg of evening primrose oil it has a lubricating effect. I think this is why so many women are passionate about it. You don't get the same effect from fish oil. However, I recently read a study that advises against over consuming omega 6 oils in ratio to omega 3 oils. Is evening primrose oil bad for the heart?
   A. We have not seen any evidence that small or reasonable amounts of evening primrose oil supplements are harmful to the cardiovascular system as long as people are ingesting a good amount of fish or omega-3 fatty acids.

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