The Omega-3 Fatty Acid Frequently Asked Questions Page

What Are Omega-3 Fatty Acids?

Everyone has heard about Omega-3 fatty acids, but not many know just what they are, which ones are important, and the specific roles each one plays in our overall health. While it is often commented that we consume too much fat in our diet, these are the fats of which we consume too little. Here we highlight the polyunsaturated fats that we should be more focused on, Omega-3s that are most commonly referred to and studied, as their benefits are being touted and studied. While there are more than the three that we will describe, the three described below have already been show to have clear roles in the body's maintenance and prevention of diseases.

What is Alpha-Linolenic Acid (ALA)?
ALA is a short-chain fatty acid that is converted by the body into the long-chain fatty acids DHA and EPA.

What is the role of ALA in the body?
ALA is known to be a source of energy for the body, and while it is converted into DHA and EPA, it is not yet definitively known how efficiently the body is at this conversion. Current research shows the body may only convert 5-10% of ALA to EPA and even less, only .01-5%, to DHA, so a person should not rely on ALA as a primary source of Omega-3 fatty acids. No research has indicated a direct role in cardiovascular or retinal health from ALA, but it plays an indirect role in the conversion to the long-chain fatty acids. While some studies have even shown a potential link in the progression of late-stage prostate cancer and macular degeneration additional research has also suggested potential neuroprotective effects of ALA in in-vivo models of both global ischemia and KA-induced epilepsy.

What is Docosahexaenoic Acid (DHA)?
DHA is a long-chain fatty acid and and is found abundantly in the brain, eyes, and nervous system. It plays an important role in the structural integrity of these parts of the body is required for their proper functioning. It is also found in breast milk, and is now included in many baby formulas and sold in supplements for pregnant women for this reason.

What is the role of DHA in the body?
DHA is required for proper brain function and development as well as being necessary for visual acuity, and it is the primary fatty acid in the phospholipids in the brain and retina. Low levels of DHA in the blood have also been shown to be related to low serotonin levels in the brain, which can affect mood. DHA is especially important to developing children as the brain and other parts of the body grow and develop. Higher level of DHA have also been shown to reduce triglycerides as well as increasing the particle size of a person's Low Density Lipoproteins (LDL), the "bad" cholesterol, which has been shown to reduce the risk of heart disease. DHA is therefore a key component in the central nervous system as well as maintaining proper cardiovascular health.

What is Eicosapentaenoic Acid (EPA)?
EPA is another long-chain Omega-3 fatty acid that is important for human health, however unlike DHA, it is not stored in the body and therefore must be consumed on a regular and ongoing basis.

What is the role of EPA in the body?
Similar to DHA, EPA plays a significant role in reducing the triglyceride level in the blood, has mild blood thinning properties and may reduce the risk of blood clots. By moderating the body's immune response, EPA can also reduce chronic inflammation, which can lead to a reduction in pain and swelling of the joints. While some studies have indicated that EPA consumption may play a role in mental health, more studies are needed to draw any definitive conclusions, however preliminary studies have indicated a link between a lack of Omega-3 consumption and depression.

Sources

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Su HM, Huang MD, Saad NM, et al. Fetal baboons convert 18:3n-3 to 22:6n-3 in vivo. A stable isotope tracer study. J Lipid Res, 2001. 42:581-6.

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Inger Lauritzen, Nicolas Blondeau, Catherine Heurteaux, Catherine Widmann, Georges Romey and Michel Lazdunski (2000). "Polyunsaturated fatty acids are potent neuroprotectors". The EMBO Journal 19 (8): 1784-1793.

Cambridge Applied Polymers Ltd. (04 April 2006). Latest Publications on the Link between DHA and Intelligence / The Brain.

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