Facts on Omega 3 Fatty Acids

Despite popular notions that people should avoid eating fats, these nutrients are vital components of a well-balanced diet. You cannot remain healthy without regularly consuming some fats. For example, omega-3 fatty acids are special types of fats, or lipids, which have been attributed with a variety of beneficial effects. In fact, according to Elson Haas, M.D., author of "Staying Healthy with Nutrition," it is difficult to imagine any health problem that isn't somehow related to improper ratios of omega fatty acids in your body.

Essentials

Any nutrient that is not synthesized within your body but that is necessary for your survival is called an "essential" nutrient. Such nutrients must be obtained from your diet. Only one omega-3 fatty acid -- alpha-linolenic acid or ALA -- has been deemed essential for human health. Linoleic acid, an omega-6 fatty acid, is the only other essential fatty acid, or EFA, that you must obtain from dietary sources. While most people get plenty of linoleic acid from their food on a daily basis, ALA is much more difficult to obtain from the typical American menu.

Conversion

Through a series of metabolic steps, ALA is converted to two other important omega-3 fatty acids, eicosapentaenoic acid, or EPA, and docosahexaenoic acid, or DHA. Some scientists believe that this conversion occurs relatively readily in your body and that additional supplementation with DHA and EPA is unnecessary; others feel that this process is remarkably inefficient in humans. Experts in the latter group recommend routine supplementation of DHA and EPA from fish oils, particularly if you have health problems such as diabetes or heart disease that might benefit from higher levels of omega-3 fatty acids, according to a 2009 "U.S. News and World Report" article, Fish Oil Supplements, EPA, DHA, and ALA: Does Your Omega-3 Source Matter? Vegans might be more efficient at converting ALA to EPA and DHA than non-vegans as the enzymatic pathway for this process may be "up-regulated" in persons whose intake of animal-derived lipids is negligible.

Functions

Omega-3 fatty acids are intermediaries in the production of a class of chemicals called eicosanoids, which include the prostaglandins, prostacyclins, thromboxanes and leukotrienes. This group of molecules is involved in a wide array of physiologic processes, including blood clotting, fluid and electrolyte balance, modulation of inflammation, smooth muscle function, blood vessel dilation and constriction, digestion, fertility, normal pregnancy, labor and delivery, blood pressure control and maintaining the integrity of the stomach lining. Although data is incomplete, EPA and DHA have been credited with a number of health benefits, such as protection from cardiovascular disease and some forms of cancer, amelioration of depression and other mental illnesses, improvement of rheumatoid arthritis and similar inflammatory conditions and slowing of age-related mental decline, according to the DHA/EPA Omega-3 Institute.

Sources

ALA is found in small amounts in some cold-water fish and in wheat germ, canola oil and walnuts. It is present in larger amounts in certain sea vegetables and in the seeds and oils from chia, pumpkin, flax and fenugreek. DHA and EPA are fairly abundant in the oils from cold-water fish, such as salmon, mackerel, cod, trout or halibut, but regular fish or fish oil consumption raises the specter of mercury or PCB contamination. DHA and EPA are also available from algal sources, eliminating the risk of contamination and allowing vegetarians to supplement their diets with these important omega-3 fatty acids.

Recommendations

If you don't want to rely on dietary sources and wish to take an omega-3 supplement, a reasonable approach is to use a combination of plant and fish or algae oils. This would furnish ALA, EPA and DHA and eliminate concerns about inefficient conversion. According to the U.S. News and World Report article, Mayo Clinic experts recommend that you should look for a supplement that offers a 3-to-2 ratio of EPA to DHA, or vice versa, as these are the combinations that have conferred health benefits in studies. About 500 to 1,000 mg of omega-3s daily is a good dosage range if you don't have any cardiovascular risk factors. People with health issues can take larger doses on their doctors' recommendations, but daily doses greater than 3,000 mg can increase your risk for bleeding. If you're put off by the "fish-oil burp," you can take your pills with food or chill them in the freezer prior to taking them.