Omega-6 essential fatty acids, found in polyunsaturated vegetable oils, are generally necessary for stimulating skin and hair growth, regulating metabolism, promoting the transport of fatty acids from the liver to the tissues, and maintaining reproductive performance. Researchers believe they play an important role in reducing the risk of heart disease, cancer, and stroke. Yet experts estimate that up to 80% of Americans consume an insufficient quantity of omega-6 fatty acids.

The omega-6 fatty acids offer a variety of potential therapeutic uses, particularly for patients with the following conditions:

• Rheumatoid arthritis: Omega-6 acids may reduce inflammation.
• Diabetes: Omega-6 fatty acid supplementation may assist nerve function and help prevent nerve disease in diabetics.
• Cancer: Gamma-linolenic acid (GLA) of the omega-6 series may suppress tumor growth and metastasis (spread), particularly in breast cancer and melanoma.
• Heart disease: GLA may prevent heart disease by reducing atherosclerosis ("hardening of the arteries") and lowering blood pressure.
• Eye disease: GLA may be beneficial in dry-eye conditions. 
• Osteoporosis: GLA may help maintain or increase bone mass. 

Omega-6 fatty acid may also be beneficial in persons with anorexia nervosa to replenish essential fatty acid deficiencies.

The American diet provides more than 10 times the needed amount of omega-6 oils in the form of linoleic acid. This is because it comprises the primary oil ingredient added to most processed foods and are found in commonly used cooking oils, such as sunflower oil, safflower oil, corn oil, and soybean oil. However, our consumption of refined fats and oils actually inhibits our body's ability to use the essential fatty acids we consume.

Omega-6 fatty acids are found in the plant seed oils of evening primrose, black currant, borage, and fungal oils.

Arachidonic acid of the omega-6 series is found in egg yolk, organ meats, and other animal-based foods.

Omega-6 fatty acids are commercially available in oils that contain linoleic acid and gamma-linolenic acid.

For general health, there should be a balance between omega-6 and omega-3 fatty acids; the ratio should be in the range of 4:1; the typical North American diet, however, normally provides ratios from 14:1 or 20:1.

Pediatric

Although dietary guidelines as described have been suggested, there are no reports to date about the therapeutic use of omega-6 fatty acids in children.

Adult

• The recommended dosage for rheumatoid arthritis is 1,400 mg per day of GLA.
• Supplementation with 480 mg of GLA per day for diabetes is recommended.
• Studies have suggested that up to 2,800 mg of GLA per day is well tolerated.

Dietary sources of omega-6 acids appear to be completely nontoxic.

Taking omega-6 fatty acids during therapy with cyclosporine, a medication used to suppress the immune system, may increase the immunosuppressive effects of this medication. Consult your healthcare provider before using omega-6 fatty acids during cyclosporine therapy.

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