Gamma-linolenic acid (GLA) is the essential fatty acid found in particular abundance in evening primrose oil, also known as EPO. GLA is an n-6 essential fatty acid. The usual dividing line for classifying essential fatty acids is that n-6 essential fatty acids turn into the hormones that cause inflammation and n-3 essential fatty acids turn into the hormones that stop inflammation, but GLA is an exception to the rule. It is chemically similar to the fatty acids in lunch meat, ham, sausage, and eggs that are transformed into compounds that cause inflammation, and interacts with enzymes needed to make the inflammatory hormones. By tying up the enzymes that otherwise would be creating inflammatory chemicals, GLA stops inflammation.
GLA was first discovered in evening primrose oil, but is also found in hempseed oil, blackcurrant oil, borage seed oil, and spirulina.
GLA's anti-inflammatory action is useful in treating diabetic neuropathy, but the effects may not be noticed for up to six months, and they may not be noticed at all in diabetics who eat vegan diets. The supplement is also more useful for diabetics who have poorly controlled blood sugars than it is for diabetics who have well-controlled blood sugars. Studies with animals suggest that GLA doesn't help neuropathy all over the body. It's relatively helpful for neuropathy in the limbs, penis, and digestive tract, but not very helpful for neuropathy causing racing heart or slow digestion.
A typical dosage of GLA is 360 to 480 mg a day, taken in encapsulated form. Some people experience mild stomach upset in the form of burping, belching, or loose stools when they first take GLA. These side effects are mild and usually go away after the second or third dose. If unpleasant side effects persist, however, discontinue the supplement.
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