Omega-6 Fatty Acid

Latest Edit: Hector 2014-02-14 (EDT)

Omega-6 fatty acids belong to a group of essential, unsaturated fatty acids that have their first carbon-carbon double bond at the sixth carbon unit from the end methyl group. Dietary omega-6 fatty acids are considered polyunsaturated fatty acids (PUFAs) due to the fact that they have more than one double-bond. Omega-6 fatty acids are found rich in seeds or nuts, as well as in refined vegetable oils such as soy oil. The balance of omega-6 to omega-3 oils is important for prostaglandin metabolism. Prostaglandins are hormone-like molecules which are derived from 20-carbon chain fatty acid containing three, four, or five double bonds. They are important for the regulation of inflammation, pain, swelling, blood pressure, heart function, gastrointestinal function and secretions, kidney function and fluid balance, and blood clotting and platelet aggregation to name a few.,

Food Sources

Sources of linoleic acid include safflower oil (75%), evening primrose oil (65-73%), sunflower oil (63-69%), wheat germ oik (55%), hempseed oil (54%), corn oil (53%), soybean oil (51%), and canola oil 19-24%). Oils that contain gamma-linolenic acid (GLA) include borage seed oil (23%), black currant seed oil (15-19%), and evening primrose oil (9%).

Uses

The following is a list of the primary uses for omega-6 fatty acids :

• Cardiovascular Disease (CVD): The correlation between whole blood fatty acids and cardiovascular risk has been identified through numerous clinical studies. One study found that total omega-3 PUFA and otal omega-6 PUFA was lower in patients who had suffered from a myocardial infarction or heart attack. This data supports the association of whole blood percentage levels of total omega-3 and total omega-6 with cardiovascular risk.

• Atherosclerosis/ischemic heart disease: Some studies have found that individual n-3 and n-6 PUFAs are inversely associated with certain ischemic stroke subtypes. On the other hand, individual serum trans, saturated, and monounsaturated fatty acids have been found to be positively associated with ischemic heart disease.
• Hypercholesterolemia: One study found that adopting a lipid-lowering diet high in n-6 PUFA can have an immediate effect on lowering plasma cholesterol concentration, of which the full effect can be achieved within two weeks.
• Hypertension: Dietary PUFAs have been found to be associated with a lower prevalence of hypertension.

• Dermatological

• Eczema: An increased intake of omega-6 PUFAs and decreased intake of omega-3 PUFAs has been found to be positively associated with eczema.
• Pruritis
• Scleroderma
• Seborrheic dermatitis of infancy

• Neurological

• Dyslexia: Omega-6 and Omega-3 PUFAs have been found to play an important role in the normal development and functioning of the brain and central nervous system. A number of observational studies have found that neurocognitive disorders such as attention-deficit hyperactivity disorder (ADHD), dyslexia, dyspraxia, and autism spectrum disorders are often associated with either a lack of supply or impaired metabolism of PUFAs.
• Essential tremor
• Multiple sclerosis: Findings from in vitro and in vivo studies in multiple sclerosis indicate that a beneficial anti-inflammatory and disease-modifying effect exists with the intake of polyunsaturated fatty acids.

Prescribing Considerations

The recommended dosages have not yet been established. To determine what your specific requirements are talk to your naturopathic doctor or other trained medical professional.

• For patients with clinical signs of EFA deficiency, which includes dry flaky skin, dry hair, and brittle nails, sunflower oil or safflower oil in dosages ranging from 1 teaspoon per day to 1 tablespoon twice a day should be taken with meals.

Deficiency Symptoms

• Dry, flaky skin
• Dermatitis
• Hair loss (females)
• Dry hair
• Brittle nails
• Increased thirst
• frequent urination
• Growth retardation in children
• Increased susceptibility to infection
• Poor wound healing

Assessment Procedure

The following are methods of assessing Omega-6 fatty acid status :

• One method involves measuring the concentrations of linoleic acid and its metabolites in plasma fatty acids or in subsets of plasma fatty acids, such as phospholipids and triglycerides.
• An increased concentration of a specific omega-9 fatty acid, known as 5,8,11 eicosatrienoic acid (or Mead acid) in plasma fatty acid fractions can indicate a deficiency of both omega-6 and omega-3 EFAs. Mead acid is formed by the action of desaturase enzymes on the omega-9 fatty acid, oleic acid. However, these enzymes act preferentially on omega-6 and omega-6 fatty acids, thereby producing significant amounts of Mead acid in the presence of omega-6 and omega-3 deficiency.

Safety

The safety precautions of Omega-6 fatty acids include :

• Rare side effects from the consumption of excessive doses such as diarrhea or other gastrointestinal symptoms.
• Evening primrose oil has been reported to exacerbate temporal lobe epilepsy, and on rare occasions cause nausea, headaches, or increased bowel movements. It is also contraindicated in patients with epilepsy as well as the manic phase of bipolar disorder.
• Consumption of large amounts of linoleic acid and other PUFAs increases oxidative stress, which can lead to the development of various chronic diseases.

• Interactions:

• Lithium. Supplementation with 3-5 g/day of safflower oil (which contains 70-75% linoleic acid) has been found to reverse lithium induced tremor.
• Omega-3 fatty acids. Some studies have found that omega-6 and omega-3 fatty acids each decrease tissue levels and interfere with metabolism of the other.
• Vitamin E. Consumption of large amounts of linoleic acid or other PUFAs has been found to increase the requirement for vitamin E by 50%.