Comprehensive information about GLA (Gamma-linolenic acid) for the treatment of ADHD, alcoholism and weight loss. Learn about the usage, dosage, side-effects of GLA.
- Dietary Sources
- Available Forms
- How to Take It
- Possible Interactions
- Supporting Research
Gamma-linolenic acid (GLA) is an essential fatty acid (EFA) in the omega-6 family that is found primarily in plant-based oils. EFAs are essential to human health but cannot be made in the body. For this reason, they must be obtained from food. EFAs are needed for normal brain function, growth and development, bone health, stimulation of skin and hair growth, regulation of metabolism, and maintenance of reproductive processes.
Linoleic acid (LA), another omega-6 fatty acid, is found in cooking oils and processed foods and converted to GLA in the body. GLA is then broken down to arachidonic acid (AA) and/or another substance called dihomogamma-liolenic acid (DGLA). AA can also be consumed directly from meat, and GLA is available directly from evening primrose oil (EPO), black currant seed oil, and borage oil. Most of these oils also contain some linoleic acid.
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The average North American diet provides more than 10 times the necessary amount of linoleic acid and tends to have too much omega-6 fatty acids compared to omega-3 fatty acids, another important class of EFAs. In fact, for optimum health, the ratio of omega-6 to omega-3 fatty acids should be between 1:1 and 4:1. The typical North American and Israeli diets are usually in the range of 11:1 to 30:1. This imbalance contributes to the development of long-term diseases such as heart disease, cancer, asthma, arthritis, and depression as well as, possibly, increased risk of infection.
Interestingly, not all omega-6 fatty acids behave the same. Linoleic acid (not to be confused with alpha-linolenic acid, which is in the omega-3 family) and arachidonic acid (AA) tend to be unhealthy because they promote inflammation, thereby increasing the risk of the diseases mentioned when consumed in excess. In contrast, GLA may actually reduce inflammation.
Much of the GLA taken from the oils mentioned or as a supplement is not converted to AA, but rather to DGLA. DGLA competes with AA and prevents the negative inflammatory effects that AA would otherwise cause in the body. Having adequate amounts of certain nutrients in the body (including magnesium, zinc, and vitamins C, B3, and B6) helps to promote the conversion of GLA to DGLA rather than AA.
It is important to know that many experts feel that the science supporting the use of omega-3 fatty acids to reduce inflammation and prevent diseases is much stronger than the information regarding use of GLA for these purposes. Two important, and most studied, omega-3 fatty acids include eicosopentaenoic acid (EPA) and docosahexaenoic acid (DHA), both found in fish and fish oils.
Some clinicians and preliminary research suggest that GLA may be useful for the following purposes:
Omega-6 fatty acid supplementation, in the form of GLA from EPO or other sources may assist nerve function and help prevent nerve disease experienced by those with diabetes (called peripheral neuropathy and felt as numbness, tingling, pain, burning, or lack of sensation in the feet and/or legs).
GLA may be beneficial in dry-eye conditions such as SjÃ¶gren's syndrome (a condition with symptoms of dry eyes, dry mouth, and, often, arthritis).
A deficiency in essential fatty acids (including GLA and EPA, an omega-3 fatty acid) can lead to severe bone loss and osteoporosis. Studies have shown that supplements of GLA and EPA together help maintain or increase bone mass. Essential fatty acids may also enhance calcium absorption, increase calcium deposits in bones, diminish calcium loss in urine, improve bone strength, and enhance bone growth, all of which may contribute to improved bone mass and, therefore, strength.
Although EPO has gained some popularity for treating hot flashes, the research to date has not demonstrated a benefit of GLA or EPO over taking a placebo. With that said, there are individual women who report improvement; therefore, it may be worthwhile to talk to your doctor about whether it is safe for you to try EPO or another form of GLA supplements to alleviate hot flashes.
Premenstrual Syndrome (PMS)
Although results of studies have been mixed, some women find relief of their PMS symptoms when using GLA supplements from EPO or another source. The symptoms that seem to be helped the most are breast tenderness and feelings of depression as well as irritability and swelling and bloating from fluid retention. Breast tenderness from causes other than PMS may also improve with use of GLA.
- Created: 31 October 2008
- Last Updated: 17 July 2014